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                                                                    EXHIBIT 99.5

                                  RADIATA, INC.

                             1999 STOCK OPTION PLAN



1. ADOPTION AND PURPOSE OF THE PLAN. This stock option plan, to be known as the
"Radiata, Inc. 1999 Stock Option Plan" (but referred to herein as the "PLAN")
has been adopted by the board of directors (the "BOARD") of Radiata, Inc., a
Delaware corporation (the "COMPANY"), and is subject to the approval of its
stockholders pursuant to section 7 below. The purpose of this Plan is to advance
the interests of the Company and its stockholders by enabling the Company to
attract and retain qualified directors, officers, employees, independent
contractors, consultants and advisers by providing them with an opportunity for
investment in the Company. The options that may be granted hereunder ("OPTIONS")
represent the right by the grantee thereof (each, including any permitted
transferee pursuant to section 6.7(c) below, an "OPTIONEE") to acquire shares of
the Company's common stock ("SHARES" which if acquired pursuant to the exercise
of an Option will be referred to as "OPTION SHARES") subject to the terms and
conditions of this Plan and a written agreement between the Company and the
Optionee to evidence each such Option (an "OPTION AGREEMENT").

2. CERTAIN DEFINITIONS. The defined terms set forth in Exhibit A attached hereto
and incorporated herein (together with other capitalized terms defined elsewhere
in this Plan) will govern the interpretation of this Plan.

3. ELIGIBILITY. The Company may grant Options under this Plan only to (i)
persons who, at the time of such grant, are directors, officers, and employees
of the Company and/or any of its Subsidiaries, and (ii) natural persons who at
the time of such grant, are independent contractors, consultants or advisers of
the Company and/or any of its Subsidiaries and who perform bona fide services on
its behalf other than in connection with capital-raising transactions
(collectively, "ELIGIBLE PARTICIPANTS"). No person will be an Eligible
Participant following his or her Termination of Eligibility Status and no Option
may be granted to any person other than an Eligible Participant. There is no
limitation on the number of Options that may be granted to an Eligible
Participant.

4. OPTION POOL; SHARES RESERVED FOR OPTIONS. In no event will the Company issue,
in the aggregate, more than FIVE MILLION TWO HUNDRED FIFTY THOUSAND (5,250,000)
Shares (the "Option Pool") pursuant to the exercise of all Options granted under
this Plan, exclusive of those Option Shares that may be reacquired by the
Company by repurchase or otherwise; provided that in order to comply with the
requirements of Section 260.140.45 of Title 10 of the California Code of
Regulations (the "30% Rule"), at no time will the total number of Shares that
are issuable upon the exercise of all outstanding Options granted under this
Plan or under any other outstanding options or warrants issued by the Company
and the total number of Shares provided for under any stock bonus or similar
plan of the Company in the aggregate exceed 30% of the total number of then
issued and outstanding Shares of the Company (or such higher percentage as has
been approved by the holders of at least two-thirds of the outstanding Shares of
the Company (including all securities convertible into Shares) entitled to
vote), as calculated in accordance with the conditions and exclusions of the 30%
Rule. At all times while Options granted under this Plan are outstanding, the
Company will reserve for issuance for the purposes hereof a sufficient number of
authorized and unissued Shares to fully satisfy the Company's obligations under
all such outstanding Options.

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5. ADMINISTRATION. This Plan will be administered and interpreted by the Board,
or by a committee consisting of two or more members of the Board, appointed by
the Board for such purpose (the Board, or such committee, referred to herein as
the "ADMINISTRATOR"). Subject to the express terms and conditions hereof, the
Administrator is authorized to prescribe, amend and rescind rules and
regulations relating to this Plan, and to make all other determinations
necessary or advisable for its administration and interpretation. Specifically,
the Administrator will have full and final authority in its discretion, subject
to the specific limitations on that discretion as are set forth herein and in
the Articles of Incorporation and Bylaws of the Company, at any time:

                (a) to select and approve the Eligible Participants to whom
        Options will be granted from time to time hereunder;

                (b) to determine the Fair Market Value of the Shares as of the
        Grant Date for any Option that is granted hereunder;

                (c) with respect to each Option it decides to grant, to
        determine the terms and conditions of that Option, to be set forth in
        the Option Agreement evidencing that Option (the form of which also
        being subject to approval by the Administrator), which may vary from the
        "default" terms and conditions set forth in section 6 below, except to
        the extent otherwise provided in this Plan, including, without
        limitation, as follows:

                        (i) the total number of Option Shares that may be
                acquired by the Optionee pursuant to the Option;

                        (ii) if the Option satisfies the conditions under
                Section 422(b) of the Code, whether the Option will be treated
                as an ISO;

                        (iii) the per share purchase price to be paid to the
                Company by the Optionee to acquire the Option Shares issuable
                upon exercise of the Option (the "OPTION PRICE"), provided that
                the Option Price will not be less than 85% of the Fair Market
                Value of the Shares as of the Grant Date, unless the Optionee is
                a 10% stockholder, in which case the Option Price will not be
                less than 110% of such Fair Market Value;

                        (iv) the maximum period or term during which the Option
                will be exercisable (the "OPTION TERM"), provided that in no
                event may the Option Term be longer than 10 years from the Grant
                Date;

                        (v) the maximum period following any Termination of
                Eligibility Status, whether resulting from an Optionee's death,
                disability or any other reason, during which period (the "GRACE
                PERIOD") the Option will be exercisable, subject to Vesting and
                to the expiration of the Option Term, provided that in no event
                may the Administrator designate a Grace Period that is shorter
                than six months after such Termination of Eligibility Status by
                reason of the Optionee's death or disability, or 30 days after
                such Termination of Eligibility for any other reason, except in
                the event of a Termination for Cause, in which case no Grace
                Period will be required (i.e., the Option will terminate
                immediately);

                        (vi) whether to accept a promissory note or other form
                of legal consideration in addition to cash as payment of all or
                a portion of the Option Price


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                and/or Tax Withholding Liability to be paid by the Optionee upon
                the exercise of an Option granted hereunder;

                        (vii) the conditions (e.g., the passage of time or the
                occurrence of events), if any, that must be satisfied prior to
                the vesting of the right to exercise all or specified portions
                of an Option (such portions being described as the number of
                Option Shares, or the percentage of the total number of Option
                Shares that may be acquired by the Optionee pursuant to the
                Option; the vested portion being referred to as a "VESTED
                OPTION" and the unvested portion being referred to as an
                "UNVESTED OPTION"), provided that no such conditions (except an
                Optionee's Termination of Eligibility Status, after which no
                Unvested Option will become a Vested Option) may be imposed
                which prevents an Optionee who is an employee, but who is
                neither an officer or director, of the Company or any of its
                Subsidiaries, from purchasing at least 20% of the Option Shares
                initially subject to the Option as of the first anniversary of
                the Grant Date, and as of each anniversary thereafter, such that
                by the fifth anniversary of the Grant Date (assuming no such
                Termination of Eligibility Status) the entire Option would be
                deemed a Vested Option; and

                        (viii) in addition, or as an alternative, to imposing
                conditions on the right to exercise an Option as provided in
                section 5(c)(vii) above, whether a Holder may exercise an
                Unvested Option and whether any portion of the Option Shares
                acquired by an Optionee upon exercise of an Option will be
                subject to repurchase by the Company or its assigns pursuant to
                section 6.8(c) below at the Option Price paid for such Shares or
                at some other price that may be less than the Fair Market Value
                of such Shares (such Shares, if subject to repurchase at less
                than Fair Market Value, being referred to as "UNVESTED SHARES")
                following a Termination of Eligibility Status or other
                designated event, and the conditions (e.g., the passage of time
                or the occurrence of events), if any, that must be satisfied for
                such Shares to be no longer subject to such right of repurchase
                at less than Fair Market Value (such Shares being referred to as
                "VESTED SHARES"); provided that no such conditions (except an
                Optionee's Termination of Eligibility Status, after which no
                Unvested Shares will become Vested Shares) may be imposed which
                prevent Unvested Shares held by an employee, who is neither an
                officer or director, of the Company and/or any of its
                Subsidiaries, from becoming Vested Shares at the rate of at
                least twenty percent (20%) per year following the Grant Date,
                such that by the fifth anniversary of the Grant Date (assuming
                no earlier Termination of Eligibility Status) all of the Shares
                would be deemed Vested Shares; and

                (d) to delegate all or a portion of the Administrator's
        authority under sections 5(a), (b) and (c) above to one or more members
        of the Board who also are executive officers of the Company, and subject
        to such restrictions and limitations as the Administrator may decide to
        impose on such delegation.

6. DEFAULT TERMS AND CONDITIONS OF OPTION AGREEMENTS. Unless otherwise expressly
provided in an Option Agreement based on the Administrator's determination
pursuant to section 5(c) above, the following terms and conditions will be
deemed to apply to each Option as if expressly set forth in the Option
Agreement:


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        6.1 ISO. No Option will be treated as an ISO unless treatment as an ISO
is expressly provided for in an Option Agreement and such Option satisfies the
conditions of Section 422(b) of the Code.

        6.2 Option Term. The Option Term will be for a period of 10 years
beginning on the Grant Date, except that in the case of an ISO granted to a 10%
stockholder, the Option Term will be for a period of 5 years beginning on the
Grant Date.

        6.3 Grace Periods. Following a Termination of Eligibility Status:

                (a) the Grace Period will be sixty (60) days, unless the
        Termination of Eligibility Status is a result of a Termination for Cause
        or the death or disability of the Optionee;

                (b) the Grace Period will be six months if the Termination of
        Eligibility Status is a result of the death or disability of the
        Optionee; and

                (c) the Option will terminate, and there will be no Grace
        Period, effective immediately as of the date and time of a Termination
        for Cause of the Optionee, regardless of whether the Option is Vested or
        Unvested.

        6.4 Vesting. The Option initially will be deemed an entirely Unvested
Option, but portions of the Option will become a Vested Option on the following
schedule:

                (a) twenty-five percent (25.0%) will become a Vested Option as
        of the first anniversary of the "Vesting Start Date" specified in the
        Option Agreement (which may be earlier but may not be later than the
        Grant Date specified therein); and

                (b) two and one-twelfth percent (2.0833%) of the Option will
        become a Vested Option as of the end of each month thereafter;

provided that the Optionee does not suffer a Termination of Eligibility Status
prior to each such vesting date and provided further that additional vesting
will be suspended during any period while the Optionee is on a leave of absence
from the Company or its Subsidiaries, as determined by the Administrator.

                (c) Subject to Section 6.3 above, A Holder may exercise any
        portion of an Unvested Option at any time.

        6.5 Exercise of the Option; Issuance of Share Certificate.

                (a) The portion of the Option that is a Vested Option may be
        exercised by giving written notice thereof to the Company, on such form
        as may be specified by the Administrator, but in any event stating: the
        Optionee's intention to exercise the Option; the date of exercise; the
        number of full Option Shares to be purchased (which number will be no
        less than 100 Shares, without regard to adjustments to the number of
        Shares subject to the Option pursuant to section 8 below, or, if less,
        all of the remaining Shares subject to the Option); the amount and form
        of payment of the Option Price; and such assurances of the Optionee's
        investment intent as the Company may require to ensure that the
        transaction complies in all respects with the requirements of the 1933
        Act and other applicable securities laws. The notice of exercise will be
        signed by the person or persons exercising the Option. In the event that
        the Option is being exercised by the representative of the


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        Optionee, the notice will be accompanied by proof satisfactory to the
        Company of the representative's right to exercise the Option. The notice
        of exercise will be accompanied by full payment of the Option Price for
        the number of Option Shares to be purchased, in United States dollars,
        in cash, by check made payable to the Company, or by delivery of such
        other form of payment (if any) as approved by the Administrator in the
        particular case.

                (b) To the extent required by applicable federal, state, local
        or foreign law, and as a condition to the Company's obligation to issue
        any Shares upon the exercise of the Option in full or in part, the
        Optionee will make arrangements satisfactory to the Company for the
        payment of any applicable Tax Withholding Liability that may arise by
        reason of or in connection with such exercise. Such arrangements may
        include, in the Company's sole discretion, that the Optionee tender to
        the Company the amount of such Tax Withholding Liability, in cash, by
        check made payable to the Company, or in the form of such other payment
        as may be approved by the Administrator, in its discretion pursuant to
        section 5(c)(vi) above.

                (c) After receiving a proper notice of exercise and payment of
        the applicable Option Price and Tax Withholding Liability, the Company
        will cause to be issued a certificate or certificates for the Option
        Shares as to which the Option has been exercised, registered in the name
        of the person rightfully exercising the Option and the Company will
        cause such certificate or certificates to be delivered to such person.

        6.6 Compliance with Law. Notwithstanding any other provision of this
Plan, Options may be granted pursuant to this Plan, and Option Shares may be
issued pursuant to the exercise thereof by an Optionee, only after and on the
condition that there has been compliance with all applicable foreign, federal
and state securities laws. The Company will not be required to list, register or
qualify any Option Shares upon any securities exchange, under any applicable
state, federal or foreign law or regulation, or with the Securities and Exchange
Commission or any state agency, or secure the consent or approval of any
governmental regulatory authority, except that if at any time the Board
determines, in its discretion, that such listing, registration or qualification
of the Option Shares, or any such consent or approval, is necessary or desirable
as a condition of or in connection with the exercise of an Option and the
purchase of Option Shares thereunder, that Option may not be exercised, in whole
or in part, unless and until such listing, registration, qualification, consent
or approval is effected or obtained free of any conditions that are not
acceptable to the Board, in its discretion. However, the Company will seek to
register or qualify with, or as may be provided by applicable local law, file
for and secure an exemption from such registration or qualification requirements
from, the applicable securities administrator and other officials of each
jurisdiction in which an Eligible Participant would be granted an Option
hereunder prior to such grant.

        6.7 Restrictions on Transfer.

                (a) Options Nontransferable. No Option will be transferable by
        an Optionee otherwise than by will or the laws of descent and
        distribution. During the lifetime of a natural person who is granted an
        Option under this Plan, the Option will be exercisable only by him or
        her. Notwithstanding anything else in this Plan to the contrary, no
        Option Agreement will contain any provision which is contrary to, or
        which modifies, the provisions of this section 6.7(a).


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                (b) Prohibited Transfers. Prior to the Initial Public Offering,
        no Holder of any Option Shares may Transfer such Shares, or any interest
        therein (i) except as expressly provided in this Plan, and (ii) other
        than in full compliance with all applicable securities laws and any
        applicable restrictions on Transfer provided in the Company's Articles
        of Incorporation and/or Bylaws, which will be deemed incorporated by
        reference into this Plan. All Transfers of Option Shares not complying
        with the specific limitations and conditions set forth in this section
        6.7 and section 6.8 below are expressly prohibited. Any prohibited
        Transfer is void and of no effect, and no purported transferee in
        connection therewith will be recognized as a Holder of Option Shares for
        any purpose whatsoever. Should such a Transfer purport to occur, the
        Company may refuse to carry out the Transfer on its books, attempt to
        set aside the Transfer, enforce any undertakings or rights under this
        Plan, or exercise any other legal or equitable remedy.

                (c) Permitted Transfers. In the case of a Permitted Transfer,
        the rights of first refusal and purchase of the Company set forth in
        sections 6.8(a) and 6.8(b) below will not apply. For such purposes, a
        "PERMITTED TRANSFER" means any of the following: (i) a Transfer by will
        or under the laws of descent and distribution; or (ii) a Transfer by a
        Holder of Option Shares to his or her ancestors, descendants or spouse
        (other than pursuant to a decree of divorce, dissolution or separate
        maintenance, a property settlement, or a separation agreement or any
        similar agreement or arrangement with a spouse, except for bona fide
        estate planning purposes), or to a trust, partnership, limited liability
        company, custodianship or other fiduciary account for the benefit of the
        Holder and/or such ancestors, descendants or spouse, including any
        Transfer in the form of a distribution from any such trust, partnership,
        limited liability company, custodianship or other fiduciary account to
        any of the foregoing permitted beneficial owners or beneficiaries
        thereof.

                (d) Conditions to Transfer. It will be a condition to any
        Transfer of any Option Shares that:

                        (i) the transferee of the Shares will execute such
                documents as the Company may reasonably require to ensure that
                the Company's rights under this Plan, and any applicable Option
                Agreement, are adequately protected with respect to such Shares,
                including, without limitation, the transferee's agreement to be
                bound by all of the terms and conditions of this Plan and such
                Agreement, as if he or she were the original Holder of such
                Shares; and

                        (ii) the Company is satisfied that such Transfer
                complies in all respects with the requirements imposed by
                applicable state and federal securities laws and regulations.

                (e) Market Standoff. If in connection with any public offering
        of securities of the Company (or any Successor Entity), the underwriter
        or underwriters managing such offering so requests, then each Optionee
        and each Holder of Option Shares will agree to not sell or otherwise
        Transfer any such Shares (other than Shares included in such
        underwriting) without the prior written consent of such underwriter, for
        such period of time as may be requested by the underwriter commencing on
        the effective date of the registration statement filed with the
        Securities and Exchange Commission in connection with such offering.


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        6.8 Rights of Purchase and First Refusal. The Company will have the
following rights of purchase and first refusal with respect to Option Shares:

                (a) Right of First Refusal. If any Holder proposes to Transfer
        any Option Shares prior to the Initial Public Offering, other than in
        the case of a Permitted Transfer pursuant to section 6.7(c) above or an
        Involuntary or Donative Transfer subject to section 6.8(b) below, the
        Company will have an assignable right of first refusal to purchase such
        Shares on the terms and conditions set out in this section 6.8(a). If
        the Company (or its assignee) elects to exercise such right, it will do
        so on an all-or-nothing basis with respect to any particular Transfer of
        Shares in the following manner:

                        (i) Before any such Transfer, the Holder proposing to
                Transfer such Shares will deliver a notice of proposed Transfer
                (a "PROPOSED TRANSFER NOTICE") to the Company stating: the
                number of Option Shares that the Holder proposes to Transfer and
                the Holder's bona fide intention to Transfer such Shares; the
                names and addresses of the Holder, the proposed transferee and
                subsequently such other information regarding such transferee as
                the Company reasonably requests; the manner and date of such
                proposed Transfer; and the bona fide cash price and/or other
                consideration (and the fair market value thereof) per share, if
                any, that such Transferee has offered to pay Holder for such
                Shares (the "OFFERED PRICE") as well as such other terms,
                including payment terms, and conditions, if any, as were
                included in such offer (the "OFFERED TERMS").

                        (ii) The Company (or its assignee) may exercise its
                right of first refusal under this section 6.8(a) at any time not
                more than twenty (20) days after the Company has received the
                Proposed Transfer Notice with respect to such Shares. If the
                Company (or its assignee) elects to exercise such purchase
                rights it will do so by delivering to the Holder of such Shares
                a notice of such election and a closing date that is no more
                than thirty (30) days after receipt of the Proposed Transfer
                Notice (or such later date as the transferee may have offered or
                on which the Transfer is otherwise scheduled to occur).

                        (iii) At the closing of the sale of the Shares to the
                Company (or its assignee), to be held at its principal executive
                offices, the Company (or its assignee) will pay the Holder of
                the Shares, in cash, the purchase price equal to the Offered
                Price, subject to an appropriate adjustment to take into account
                any deferred payment terms that were included in the Offered
                Terms, except in the case of a Transfer of Option Shares without
                consideration; provided that if the Offered Price includes any
                non-cash consideration, the value thereof for purposes of this
                section 6.8(a) will be determined in good faith by the Board.

                        (iv) If the Company (including its assignees) fails or
                refuses to exercise its rights under this section 6.8(a) with
                respect to any Shares that are the subject of any Proposed
                Transfer Notice, then the Holder will have the right to Transfer
                such Shares to the transferee named in such Notice at the
                Offered Price and upon such Offered Terms as were set forth in
                such Notice; provided that such Transfer must be completed
                within ninety (90) days after the Company has received the
                Proposed Transfer Notice with respect to such Shares.


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                (b) Following an Involuntary or Donative Transfer. Following any
        Involuntary Transfer or Donative Transfer (other than a Permitted
        Transfer) of Option Shares (the "TRANSFERRED SHARES") prior to the
        Initial Public Offering, the Company will have the assignable right to
        purchase from the transferee of the Transferred Shares ("TRANSFEREE")
        all or a portion of such Shares for a purchase price that is equal to
        the Fair Market Value of those Shares as of the date of such Transfer.
        If the Company (or its assignee) elects to exercise such right, it will
        do so in the following manner:

                        (i) Promptly after such Transfer, the transferor of the
                Transferred Shares will deliver, or will cause the Transferee to
                deliver, a notice (a "COMPLETED TRANSFER NOTICE") to the Company
                stating: the number of Transferred Shares; the names and
                addresses of the transferor and the Transferee, and subsequently
                such other information regarding the Transferee as the Company
                reasonably requests; and the manner, circumstances and date of
                such Transfer.

                        (ii) The Company (or its assignee) may exercise its
                purchase rights under this section 6.8(b) at any time not more
                than ninety (90) days after the Company has received the
                Completed Transfer Notice with respect to the Transferred
                Shares. If the Company (or its assignee) elects to exercise such
                purchase rights it will do so by delivering to the Transferee a
                notice of such election, specifying the number of Transferred
                Shares to be purchased and a closing date that is no more than
                sixty (60) days after the giving of such notice.

                        (iii) At such closing, to be held at the Company's
                principal executive offices, the Company (or its assignee) will
                pay the Transferee the purchase price specified in this section
                6.8(b).

                (c) Following a Termination of Eligibility Status. Following any
        Termination of Eligibility Status of the original Holder of any Option
        Shares, the Company will have the assignable right (but not the
        obligation) to purchase all or a portion of such Shares, for a purchase
        price that is equal to (1) in the case of Unvested Shares pursuant to
        section 5(c)(viii) above, the Option Price paid for those Shares, and
        (2) in the case of Vested Shares, or Option Shares that were never
        subject to Vesting pursuant to section 5(c)(viii) above, the greater of
        (A) the Option Price paid for those Shares, or (B) the Fair Market Value
        of those Shares as of the date of such Termination of Eligibility
        Status, provided that such right to purchase Vested Shares shall
        terminate upon the Initial Public Offering. Such right will be
        exercisable in the following manner:

                        (i) The Company (or its assignee) may exercise its right
                of repurchase under this section 6.8(c) at any time not more
                than ninety (90) days after the effective date of such
                Termination of Eligibility Status (or in the case of Shares
                issued upon the exercise of Options after such Termination of
                Eligibility Status, a period of ninety (90) days after the date
                of the exercise). If the Company (or its assignee) elects to
                exercise such purchase rights it will do so by delivering to the
                Holder of such Shares a notice of such election, specifying the
                number of Shares to be purchased and a closing date that is
                within such 90-day period, provided that if the Holder of the
                Shares is not an employee of the Company or any of its
                Subsidiaries, or is an officer, director or affiliate thereof,
                the Option Agreement may provide that the period during which
                such purchase of the Shares must take place may be longer than
                90 days.


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                        (ii) At such closing, the Company (or its assignee) will
                pay the Holder of the Shares, the purchase price, as specified
                in this section 6.8(c), in cash, or by cancellation of
                indebtedness to the Company, if any, incurred by the original
                Holder of the Option Shares to purchase such Shares, or both, at
                a closing to be held at the Company's principal executive
                offices on the date specified in such notice, provided that if
                the Holder of the Shares is not an employee of the Company or
                any of its Subsidiaries, or is an officer, director or affiliate
                thereof, the Option Agreement may provide that the purchase
                price may be paid, in whole or in part, with a promissory note
                from the Company (or its assignee).

                (d)Escrow. For purposes of facilitating the enforcement of the
        restrictions on Transfer set forth in this Plan or in any Option
        Agreement, the Administrator may, at its discretion, require the Holder
        of Option Shares to deliver the certificate(s) for such Shares with a
        stock power executed by him or her and by his or her spouse (if required
        for Transfer), in blank, to the Secretary of the Company or his or her
        designee, to hold said certificate(s) and stock power(s) in escrow and
        to take all such actions and to effectuate all such Transfers and/or
        releases as are in accordance with the terms of this Plan. The
        certificates may be held in escrow so long as the Option Shares whose
        ownership they evidence are subject to any right of repurchase or first
        refusal under this Plan or under an Option Agreement, and will be
        released by the escrow holder to an Optionee (or to any permitted
        transferee of the Optionee) when they are no longer subject to any right
        of repurchase or first refusal under this Plan or under the Option
        Agreement. Each Optionee, by exercising an Option, thereby acknowledges
        that the Secretary of the Company (or his or her designee) is so
        appointed as the escrow holder with the foregoing authorities as a
        material inducement to the grant of an Option under this Plan, that the
        appointment is coupled with an interest, and that it accordingly will be
        irrevocable. The escrow holder will not be liable to any party to an
        Option Agreement (or to any other party) for any actions or omissions
        unless the escrow holder is grossly negligent relative thereto. The
        escrow holder may rely upon any letter, notice or other document
        executed by any signature purported to be genuine.

                (e) Resolution of Disputes. If there is a dispute concerning the
        fair market value of the consideration offered or accepted for the
        Option Shares or the Fair market Value of the Option Shares, in
        connection with the exercise by the Company of its rights under this
        section 6.8, the dispute will be resolved by the independent certified
        public accounting firm that audited or prepared without audit the
        Company's last regular annual financial statement and the determination
        of that firm will be binding on the parties in the absence of fraud.

        6.9 Change of Control Transactions. In the event of a Change of Control
Transaction, (i) the Company shall endeavor to cause the Successor Entity (or
its parent or its Subsidiary) in such transaction either to assume all of the
Options which have been granted hereunder and which are outstanding as of the
consummation of such transaction ("CLOSING"), or to issue (or cause to be
issued) in substitution thereof comparable options of such Successor Entity (or
of its parent or its Subsidiary) and (ii) immediately prior to such a Closing, a
portion of the Option which would otherwise then remain Unvested will become
Vested (the "Accelerated Portion") based on the following formula: for each
period of 30 days prior to the Closing that the Optionee has been an Eligible
Participant, 10% of the Option that would otherwise then remain Unvested will
become Vested, but in no event shall the Accelerated Portion of the Option
exceed 50% of the unvested shares. If the Successor Entity (or its parent or its
Subsidiary) is unwilling to either assume such Options or grant comparable
options in substitution for such Options, on terms that are acceptable


                                      -9-
<PAGE>   10

to the Company as determined by the Board in the exercise of its discretion,
then the Board may cancel all outstanding Options, and terminate this Plan,
effective as of the Closing, provided that it will notify all Optionees of the
proposed Change of Control Transaction a reasonable amount of time prior to the
Closing so that each Optionee will be given the opportunity to exercise the
Vested portion of his or her Option prior to the Closing. For purposes of this
section 6.9, the term "CHANGE OF CONTROL TRANSACTION" means a Business
Combination in which less than (50%) of the outstanding voting securities of the
Successor Entity immediately following the Closing of the Business Combination
transaction are beneficially held by those persons and entities in the same
proportion as such persons and entities beneficially held the voting securities
of the Company immediately prior to such transaction; the term "BUSINESS
COMBINATION" means a transaction or series of transactions consummated within
any period of 90 days resulting in (A) the sale of all or substantially all of
the assets of the Company, (B) a merger or consolidation or other reorganization
of which the Company or a Subsidiary is a merging party, or (C) the sale or
other change of beneficial ownership of at least fifty percent (50%) of the
outstanding voting securities of the Company.

        6.10 Additional Restrictions on Transfer; Investment Intent. By
accepting an Option and/or Option Shares under this Plan, the Optionee will be
deemed to represent, warrant and agree that, unless a registration statement is
in effect with respect to the offer and sale of Option Shares: (i) neither the
Option nor any such Shares will be freely tradeable and must be held
indefinitely unless such Option and such Shares are either registered under the
1933 Act or an exemption from such registration is available; (ii) the Company
is under no obligation to register the Option or any such Shares; (iii) upon
exercise of the Option, the Optionee will purchase the Option Shares for his or
her own account and not with a view to distribution within the meaning of the
1933 Act, other than as may be effected in compliance with the 1933 Act and the
rules and regulations promulgated thereunder; (iv) no one else will have any
beneficial interest in the Option Shares; (v) the Optionee has no present
intention of disposing of the Option Shares at any particular time; and (vi)
neither the Option nor the Shares have been qualified under the securities laws
of any state and may only be offered and sold pursuant to an exception from
qualification under applicable state securities laws.

        6.11 Stock Certificates; Legends. Certificates representing Option
Shares will bear all legends required by law and necessary or appropriate in the
Administrator's discretion to effectuate the provisions of this Plan and of the
applicable Option Agreement. The Company may place a "stop transfer" order
against Option Shares until full compliance with all restrictions and conditions
set forth in this Plan, in any applicable Option Agreement and in the legends
referred to in this section 6.11.

        6.12 Notices. Any notice to be given to the Company under the terms of
an Option Agreement will be addressed to the Company at its principal executive
office, Attention: Secretary, or at such other address as the Company may
designate in writing. Any notice to be given to an Optionee will be addressed to
him or her at the address provided to the Company by the Optionee. Any such
notice will be deemed to have been duly given if and when enclosed in a properly
sealed envelope, addressed as aforesaid, deposited, postage prepaid, in a post
office or branch post office regularly maintained by the local postal authority.

        6.13 Other Provisions. Each Option Agreement may contain such other
terms, provisions and conditions, including restrictions on the Transfer of
Option Shares, and rights of the Company to repurchase such Shares, not
inconsistent with this Plan and applicable law, as may be determined by the
Administrator in its sole discretion.


                                      -10-
<PAGE>   11

        6.14 Specific Performance. Under those circumstances in which the
Company chooses to timely exercise its rights to repurchase Option Shares as
provided herein or in any Option Agreement, the Company will be entitled to
receive such Shares in specie in order to have the same available for future
issuance without dilution of the holdings of other stockholders of the Company.
By accepting Option Shares, the Holder thereof therefore acknowledges and agrees
that money damages will be inadequate to compensate the Company and its
stockholders if such a repurchase is not completed as contemplated hereunder and
that the Company will, in such case, be entitled to a decree of specific
performance of the terms hereof or to an injunction restraining such holder (or
such Holder's personal representative) from violating this Plan or Option
Agreement, in addition to any other remedies that may be available to the
Company at law or in equity.

7. TERM OF THE PLAN. This Plan will become effective on the date of its adoption
by the Board, provided that this Plan is approved by the stockholders of the
Company (excluding Option Shares issued by the Company pursuant to the exercise
of Options granted under this Plan) within 12 months before or after that date.
If this Plan is not so approved by the stockholders of the Company within that
12-month period of time, any Options granted under this Plan will be rescinded
and will be void. This Plan will expire on the tenth (10th) anniversary of the
date of its adoption by the Board or its approval by the stockholders of the
Company, whichever is earlier, unless it is terminated earlier pursuant to
section 11 of this Plan, after which no more Options may be granted under this
Plan, although all outstanding Options granted prior to such expiration or
termination will remain subject to the provisions of this Plan, and no such
expiration or termination of this Plan will result in the expiration or
termination of any such Option prior to the expiration or early termination of
the applicable Option Term.

8. ADJUSTMENTS UPON CHANGES IN STOCK. In the event of any change in the
outstanding Shares of the Company as a result of a stock split, reverse stock
split, stock bonus or distribution, recapitalization, combination or
reclassification, appropriate proportionate adjustments will be made in: (i) the
aggregate number of Shares that are reserved for issuance in the Option Pool
pursuant to section 4 above, under outstanding Options or future Options granted
hereunder; (ii) the Option Price and the number of Option Shares that may be
acquired under each outstanding Option granted hereunder; and (iii) other rights
and matters determined on a per share basis under this Plan or any Option
Agreement evidencing an outstanding Option granted hereunder. Any such
adjustments will be made only by the Board, and when so made will be effective,
conclusive and binding for all purposes with respect to this Plan and all
Options then outstanding. No such adjustments will be required by reason of the
issuance or sale by the Company for cash or other consideration of additional
Shares or securities convertible into or exchangeable for Shares.

9. MODIFICATION, EXTENSION AND RENEWAL OF OPTIONS. Subject to the terms and
conditions and within the limitations of this Plan, the Administrator may
modify, extend or renew outstanding Options granted under this Plan, or accept
the surrender of outstanding Options (to the extent not theretofore exercised)
and authorize the granting of new Options in substitution therefor (to the
extent not theretofore exercised). Notwithstanding the foregoing, however, no
modification of any Option will, without the consent of the Optionee, alter or
impair any rights or obligations under any outstanding Option.

10. GOVERNING LAW; VENUE. The internal laws of the State of Delaware
irrespective of its choice of law principles) will govern the validity of this
Plan, the construction of its terms and the interpretation of the rights and
duties of the parties hereunder and under any Option Agreement.


                                      -11-
<PAGE>   12

Any party may seek to enforce its rights under this Plan or any Option Agreement
entered into under this Plan in any court of competent jurisdiction located
within the judicial district in which the Company or its Subsidiaries has a
regular place of business.

11. AMENDMENT AND DISCONTINUANCE. The Board may amend, suspend or discontinue
this Plan at any time or from time to time; provided that no action of the Board
will, without the approval of the stockholders of the Company, materially
increase (other than by reason of an adjustment pursuant to section 8 hereof)
the maximum aggregate number of Option Shares in the Option Pool, materially
increase the benefits accruing to Eligible Participants, or materially modify
the category of, or eligibility requirements for persons who are Eligible
Participants. However, no such action may alter or impair any Option previously
granted under this Plan without the consent of the Optionee, nor may the number
of Option Shares in the Option Pool be reduced to a number that is less than the
aggregate number of Option Shares (i) that may be issued pursuant to the
exercise of all outstanding and unexpired Options granted hereunder, and (ii)
that have been issued and are outstanding pursuant to the exercise of Options
granted hereunder.

12. INFORMATION PROVIDED BY COMPANY. Prior to the date on which the Company is
required to file its annual financial statements with the Securities and
Exchange Commission under the Securities Exchange Act of 1934, the Company
annually will provide the Company's financial statements (which statements need
not be audited) to each Optionee who is an employee of the Company or any of its
Subsidiaries, and each Optionee will, by virtue of entering into an Option
Agreement, be deemed to have agreed (and to cause any investment advisers to
whom the Optionee proposes to make such information available to agree) to keep
such information confidential and not to use, disclose or copy such information
for any purpose whatsoever other than determining whether to exercise an Option.
The Company deems such financial statements to be the valuable trade secrets of
the Company, and in the event of any wrongful use, disclosure or other breach of
the obligation to maintain the confidentiality of such financial information,
the Company may seek to enforce all of its available legal and equitable rights
and remedies, and may notify local law enforcement officials that a criminal
misappropriation of the Company's trade secrets has taken place.

13. NO STOCKHOLDER RIGHTS. No rights or privileges of a stockholder in the
Company are conferred by reason of the granting of an Option. No Optionee will
become a stockholder in the Company with respect to any Option Shares unless and
until the Option has been properly exercised and the Option Price fully paid as
to the portion of the Option exercised.

14. COPIES OF PLAN. A copy of this Plan will be delivered to each Optionee at or
before the time he, she or it executes an Option Agreement.



Date Plan Adopted by Board of Directors:      December 11, 1999

Date Plan Approved by the Stockholders:       December 21, 1999


                                      -12-
<PAGE>   13

                                  RADIATA, INC.
                             1999 STOCK OPTION PLAN

                                    EXHIBIT A
                                   DEFINITIONS

1. "10% STOCKHOLDER" means a person who owns, either directly or indirectly by
virtue of the ownership attribution provisions set forth in Section 424(d) of
the Code at the time he or she is granted an Option, stock possessing more than
10% of the total combined voting power or value of all classes of stock of the
Company and/or of its Subsidiaries.

2.  "1933 ACT" means the Securities Act of 1933, as amended.

3.  "ADMINISTRATOR" has the meaning set forth in section 5 of the Plan.

4.  "BOARD" has the meaning set forth in section 1 of the Plan.

5.  "BUSINESS COMBINATION" has the meaning set forth in section 6.9 of the Plan.

6. "CHANGE OF CONTROL TRANSACTION" has the meaning set forth in section 6.9 of
the Plan.

7.  "CLOSING" has the meaning set forth in section 6.9 of the Plan.

8. "CODE" means the Internal Revenue Code of 1986, as amended (references herein
to Sections of the Code are intended to refer to Sections of the Code as enacted
at the time of the Plan's adoption by the Board and as subsequently amended, or
to any substantially similar successor provisions of the Code resulting from
recodification, renumbering or otherwise).

9.  "COMPANY" has the meaning set forth in section 1 of the Plan.

10. "COMPLETED TRANSFER NOTICE" has the meaning set forth in section 6.8(b) of
the Plan.

11. "DISABILITY" means any physical or mental disability, which results in a
Termination of Eligibility Status under applicable law, except that for purposes
of section 6.1(c) of the Plan, the term "disability" means permanent and total
disability within the meaning of Section 22(e)(3) of the Code.

12. "DONATIVE TRANSFER" with respect to Option Shares means any voluntary
Transfer by a transferor other than for value or the payment of consideration to
the transferor.

13. "ELIGIBLE PARTICIPANTS" has the meaning set forth in section 3 of the Plan.

14. "FAIR MARKET VALUE" means, with respect to the Shares and as of the date
that is relevant to such a determination (e.g., on the Grant Date), the market
price per share of such Shares determined by the Administrator, consistent with
the requirements of Section 422 of the Code and to the extent consistent
therewith, as follows: (a) if the Shares are traded on a stock exchange on the
date in question, then the Fair Market Value will be equal to the closing price
reported by the applicable composite-transactions report for such date; (b) if
the Shares are traded over-the-counter on the date in question and are
classified as a national market issue, then the Fair Market Value will be equal
to the last-transaction price quoted by the NASDAQ system for such date; (c) if
the Shares are traded over-the-counter on the date in question but are not
classified as a national market issue, then the Fair

<PAGE>   14

Market Value will be equal to the mean between the last reported representative
bid and asked prices quoted by the NASDAQ system for such date; and (d) if none
of the foregoing provisions is applicable, then the Fair Market Value will be
determined by the Administrator in good faith on such basis as it deems
appropriate, taking into consideration the provisions of Section 260.140.50 of
Title 10 of the California Code of Regulations.

15. "GRACE PERIOD" has the meaning set forth in section 5(c)(v) of the Plan.

16. "GRANT DATE" means, with respect to an Option, the date on which the Option
Agreement evidencing that Option is entered into between the Company and the
Optionee, or such other date as may be set forth in that Option Agreement as the
"Grant Date" which will be the effective date of that Option Agreement.

17. "HOLDER" means the holder of any Option Shares.

18. "INITIAL PUBLIC OFFERING" means the closing of the first sale of securities
of the Company, or of any Successor Entity, to the public, through a firm
commitment underwriting, for an aggregate price (exclusive of underwriters'
discounts and commissions and expenses of the offering) of at least thirty
million dollars ($30,000,000), pursuant to an effective registration statement
filed with the Securities and Exchange Commission under the 1933 Act.

19. "INVOLUNTARY TRANSFER" with respect to Option Shares includes, without
limitation, any of the following: (A) an assignment of the Shares for the
benefit of creditors of the transferor; (B) a Transfer by operation of law; (C)
an execution of judgment against the Shares or the acquisition of record or
beneficial ownership of Shares by a lender or creditor; (D) a Transfer pursuant
to any decree of divorce, dissolution or separate maintenance, any property
settlement, any separation agreement or any other agreement with a spouse
(except for bona fide estate planning purposes) under which any Shares are
Transferred or awarded to the spouse of the transferor or are required to be
sold; or (E) a Transfer resulting from the filing by the transferor of a
petition for relief, or the filing of an involuntary petition against the
transferor, under the bankruptcy laws of the United States or of any other
nation.

20. "ISO" means an "incentive stock option" as defined in Section 422 of the
Code.

21. "OFFERED PRICE" has the meaning set forth in section 6.8(a) of the Plan.

22. "OFFERED TERMS" has the meaning set forth in section 6.8(a) of the Plan.

23. "OPTION AGREEMENT" has the meaning set forth in section 1 of the Plan.

24. "OPTION POOL" has the meaning set forth in section 4 of the Plan.

25. "OPTION PRICE" has the meaning set forth in section 5(c)(iii) of the Plan.

26. "OPTION SHARES" has the meaning set forth in section 1 of the Plan, provided
that for purposes of section 6.7 and section 6.8 of the Plan, the term "Option
Shares" includes all Shares issued by the Company to a Holder (or his, her or
its predecessor) by reason of such holdings, including any securities which may
be acquired as a result of a stock split, stock dividend, and other
distributions of Shares in the Company made upon, or in exchange for, other
securities of the Company.


                                       ii

<PAGE>   15

27. "OPTION TERM" has the meaning set forth in section 5(c)(iv) of the Plan.

28. "OPTIONEE" has the meaning set forth in section 1 of the Plan.

29. "OPTIONS" has the meaning set forth in section 1 of the Plan.

30. "PERMITTED TRANSFER" has the meaning set forth in section 6.7(c) of the
Plan.

31. "PLAN" has the meaning set forth in section 1 of the Plan.

32. "PROPOSED TRANSFER NOTICE" has the meaning set forth in section 6.8(a) of
the Plan.

33. "SHARES" has the meaning set forth in section 1 of the Plan.

34. "SUBSIDIARY" has the same meaning as "subsidiary corporation" as defined in
Section 424(f) of the Code.

35. "SUCCESSOR ENTITY" means a corporation or other entity that acquires all or
substantially all of the assets of the Company, or which is the surviving or
parent entity resulting from a Business Combination, as that term is defined in
section 6.9 of the Plan.

36. "TAX WITHHOLDING LIABILITY" in connection with the exercise of any Option
means all federal and state income taxes, social security tax, and any other
taxes applicable to the compensation income arising from the transaction
required by applicable law to be withheld by the Company.

37. "TERMINATION OF ELIGIBILITY STATUS" means (i) in the case of any employee of
the Company and/or any of its Subsidiaries, a termination of his or her
employment, whether by the employee or employer, and whether voluntary or
involuntary, including without limitation as a result of the death or disability
of the employee, (ii) in the case of any advisor, consultant, or independent
contractor of the Company and/or any of its Subsidiaries, the termination of the
services relationship pursuant to any contract between the parties or otherwise
under applicable law, and (iii) in the case of any director of the Company
and/or any of its Subsidiaries, the death of or resignation by the director or
his or her removal from the board in the manner provided by the articles of
incorporation, bylaws or other organic instruments of the Company or Subsidiary
or otherwise in accordance with applicable law.

38. "TERMINATION FOR CAUSE" means (i) in the case of an Optionee who is an
employee of the Company and/or any of its Subsidiaries, a termination by the
employer of the Optionee's employment for "cause" as defined by applicable law,
by any contract of employment or the Option Agreement, or if not defined
therein, pursuant to the "For Cause Standard" set forth below, (ii) in the case
of an Optionee who is or which is an advisor, consultant or independent
contractor to the Company and/or any of its Subsidiaries, a termination of the
services relationship by the hiring party for "cause" or breach of contract, as
defined by applicable law, by any contract between the parties or the Option
Agreement, or if not defined therein, pursuant to the "For Cause Standard" set
forth below, and (iii) in the case of an Optionee who is a director of the
Company and/or any of its Subsidiaries, removal of him or her from the board of
directors by action of the stockholders or, if permitted by applicable law and
the articles, bylaws or other organic documents of the Company or the
Subsidiary, as the case may be, or pursuant to applicable law, by the other
directors), in connection with the good faith determination of the board of
directors (or of the Company's or Subsidiary's stockholders if so required, but
in either case excluding the vote of the subject


                                      iii

<PAGE>   16

individual if he or she is a director or a stockholder) that the Optionee has
engaged in any acts which breach any fiduciary duty to the Company, any of its
Subsidiaries or their stockholders, or in any acts involving dishonesty or moral
turpitude or in any acts that materially and adversely affect the business,
affairs or reputation of the Company or any of its Subsidiaries (the "For Cause
Standard").

39. "TRANSFER" with respect to Option Shares, includes, without limitation, a
voluntary or involuntary sale, assignment, transfer, conveyance, pledge,
hypothecation, encumbrance, disposal, loan, gift, attachment or levy of those
Shares, including any Involuntary Transfer, Donative Transfer or transfer by
will or under the laws of descent and distribution.

40. "TRANSFEREE" has the meaning set forth in section 6.8(b) of the Plan.

41. "TRANSFERRED SHARES" has the meaning set forth in section 6.8(b) of the
Plan.

42. "UNVESTED OPTION" has the meaning set forth in section 5(c)(vii) of the
Plan.

43. "UNVESTED SHARES" has the meaning set forth in section 5(c)(viii) of the
Plan.

44. "VESTED OPTION" has the meaning set forth in section 5(c)(vii) of the Plan.

45. "VESTED SHARES" has the meaning set forth in section 5(c)(viii) of the Plan.



                                       iv
