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                                                                    EXHIBIT 99.6

                            CELLSTREAM NETWORKS INC.
                             1995 STOCK OPTION PLAN


                                   ARTICLE ONE

                               GENERAL PROVISIONS


       I.      PURPOSE OF THE PLAN

               This 1995 Stock Option Plan is intended to promote the interests
of CellStream Networks Inc., a Delaware corporation, by providing eligible
persons with the opportunity to acquire a proprietary interest, or otherwise
increase their proprietary interest, in the Corporation as an incentive for them
to remain in the service of the Corporation.

               Capitalized terms herein shall have the meanings assigned to such
terms in the attached Appendix.

      II.      ADMINISTRATION OF THE PLAN

               A. The Plan shall be administered by the Board. However, any or
all administrative functions otherwise exercisable by the Board may be delegated
to the Committee. Members of the Committee shall serve for such period of time
as the Board may determine and shall be subject to removal by the Board at any
time. The Board may also at any time terminate the functions of the Committee
and reassume all powers and authority previously delegated to the Committee.

               B. The Plan Administrator shall have full power and authority
(subject to the provisions of the Plan) to establish such rules and regulations
as it may deem appropriate for proper administration of the Plan and to make
such determinations under, and issue such interpretations of, the Plan and any
outstanding options as it may deem necessary or advisable. Decisions of the Plan
Administrator shall be final and binding on all parties who have an interest in
the Plan or any option or shares issued thereunder.

         III.  ELIGIBILITY

               A. The persons eligible to receive option grants under the Plan
are as follows:

                         (i) Employees,

                         (ii) non-employee members of the Board or the
         non-employee members of the board of directors of any Parent or
         Subsidiary, and


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                        (iii) consultants who provide services to the
         Corporation (or any Parent or Subsidiary).

               B. The Plan Administrator shall have full authority to determine
which eligible persons are to receive option grants under the Plan, the time or
times when such option grants are to be made, the number of shares to be covered
by each such grant, the status of the granted option as either an Incentive
Option or a Non-Statutory Option, the time or times at which each option is to
become exercisable, the vesting schedule (if any) applicable to the option
shares and the maximum term for which the option is to remain outstanding.

         IV.   STOCK SUBJECT TO THE PLAN

               A. The stock issuable under the Plan shall be shares of
authorized but unissued or reacquired Common Stock. The maximum number of shares
of Common Stock which may be issued over the term of the Plan shall not exceed
1,518,245 shares.

               B. Shares of Common Stock subject to outstanding options shall be
available for subsequent issuance under the Plan to the extent (i) the options
expire or terminate for any reason prior to exercise in full or (ii) the options
are cancelled in accordance with the cancellation-regrant provisions of Article
Two. All shares issued under the Plan, whether or not those shares are
subsequently repurchased by the Corporation pursuant to its repurchase rights
under the Plan, shall reduce on a share-for-share basis the number of shares of
Common Stock available for subsequent issuance under the Plan.

               C. Should any change be made to the Common Stock by reason of any
stock split, stock dividend, recapitalization, combination of shares, exchange
of shares or other change affecting the outstanding Common Stock as a class
without the Corporation's receipt of consideration, appropriate adjustments
shall be made to (i) the maximum number and/or class of securities issuable
under the Plan and (ii) the number and/or class of securities and the exercise
price per share in effect under each outstanding option in order to prevent the
dilution or enlargement of benefits thereunder. The adjustments determined by
the Plan Administrator shall be final, binding and conclusive. In no event shall
any such adjustments be made in connection with the conversion of one or more
outstanding shares of the Corporation's preferred stock into shares of Common
Stock.

                                   ARTICLE TWO

                              OPTION GRANT PROGRAM


       I.      OPTION TERMS

               Each option shall be evidenced by one or more documents in the
form approved by the Plan Administrator; provided, however, that each such
document shall comply with the terms

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specified below. Each document evidencing an Incentive Option shall, in
addition, be subject to the provisions of the Plan applicable to such options.

               A.     EXERCISE PRICE.

                      1. The exercise price per share shall be fixed by the Plan
Administrator in accordance with the following provisions:

                          (i) The exercise price per share shall not be less
         than eighty-five percent (85%) of the Fair Market Value per share of
         Common Stock on the option grant date.

                         (ii) If the person to whom the option is granted is a
         10% Stockholder, then the exercise price per share shall not be less
         than one hundred ten percent (110%) of the Fair Market Value per share
         of Common Stock on the option grant date.

                      2. The exercise price shall become immediately due upon
exercise of the option and shall, subject to the provisions of Section I of
Article Three and the documents evidencing the option, be payable in cash or
check made payable to the Corporation. Should the Common Stock be registered
under Section 12(g) of the 1934 Act at the time the option is exercised, then
the exercise price may also be paid as follows:

                          (i) in shares of Common Stock held for the requisite
         period necessary to avoid a charge to the Corporation's earnings for
         financial reporting purposes and valued at Fair Market Value on the
         Exercise Date, or

                         (ii) to the extent the option is exercised for vested
         shares, through a special sale and remittance procedure pursuant to
         which the Optionee shall concurrently provide irrevocable written
         instructions (a) to a Corporation-designated brokerage firm to effect
         the immediate sale of the purchased shares and remit to the
         Corporation, out of the sale proceeds available on the settlement date,
         sufficient funds to cover the aggregate exercise price payable for the
         purchased shares plus all applicable Federal, state and local income
         and employment taxes required to be withheld by the Corporation by
         reason of such exercise and (b) to the Corporation to deliver the
         certificates for the purchased shares directly to such brokerage firm
         in order to complete the sale.

               Except to the extent such sale and remittance procedure is
utilized, payment of the exercise price for the purchased shares must be made on
the Exercise Date.

               B. EXERCISE AND TERM OF OPTIONS. Each option shall be exercisable
at such time or times, during such period and for such number of shares as shall
be determined by the Plan


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Administrator and set forth in the documents evidencing the option. However, no
option shall have a term in excess of ten (10) years measured from the option
grant date.

               C. EFFECT OF TERMINATION OF SERVICE. The following provisions
shall govern the exercise of any options held by the Optionee at the time of
cessation of Service or death:

                          (i) Should the Optionee cease to remain in Service for
         any reason other than Disability or death, then the Optionee shall have
         a period of three (3) months following the date of such cessation of
         Service during which to exercise each outstanding option held by such
         Optionee.

                         (ii) Should such Service terminate by reason of
         Disability, then the Optionee shall have a period of six (6) months
         following the date of such cessation of Service during which to
         exercise each outstanding option held by such Optionee. However, should
         such Disability be deemed to constitute Permanent Disability, then the
         period during which each outstanding option held by the Optionee is to
         remain exercisable shall be extended by an additional six (6) months so
         that the exercise period shall be the twelve (12)-month period
         following the date of the Optionee's cessation of Service by reason of
         such Permanent Disability.

                        (iii) Should the Optionee die while holding one or more
         outstanding options, then the personal representative of the Optionee's
         estate or the person or persons to whom the option is transferred
         pursuant to the Optionee's will or in accordance with the laws of
         descent and distribution shall have a period of twelve (12) months
         following the date of the Optionee's death during which to exercise
         each such option.

                         (iv) Under no circumstances, however, shall any such
         option be exercisable after the specified expiration of the option
         term.

                          (v) During the applicable post-Service exercise
         period, the option may not be exercised in the aggregate for more than
         the number of vested shares for which the option is exercisable on the
         date of the Optionee's cessation of Service. Upon the expiration of the
         applicable exercise period or (if earlier) upon the expiration of the
         option term, the option shall terminate and cease to be outstanding for
         any vested shares for which the option has not been exercised. However,
         the option shall, immediately upon the Optionee's cessation of Service,
         terminate and cease to be outstanding to the extent it is not
         exercisable for vested shares on the date of such cessation of Service.

               D. STOCKHOLDER RIGHTS. The holder of an option shall have no
stockholder rights with respect to the shares subject to the option until such
person shall have exercised the option, paid the exercise price and become a
holder of record of the purchased shares.


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               E. UNVESTED SHARES. The Plan Administrator shall have the
discretion to grant options which are exercisable for unvested shares of Common
Stock under the Plan. Should the Optionee cease Service while holding such
unvested shares, the Corporation shall have the right to repurchase, at the
exercise price paid per share, all or (at the discretion of the Corporation and
with the consent of the Optionee) any of those unvested shares. The terms upon
which such repurchase right shall be exercisable (including the period and
procedure for exercise and the appropriate vesting schedule for the purchased
shares) shall be established by the Plan Administrator and set forth in the
document evidencing such repurchase right. The Plan Administrator may not impose
a vesting schedule upon any option grant or any shares of Common Stock subject
to the option which is more restrictive than twenty percent (20%) per year
vesting, with the initial vesting to occur one (1) year after the option grant
date. However, this minimum vesting requirement shall not be applicable with
respect to any option granted to a Highly-Compensated Person.

               F. FIRST REFUSAL RIGHTS. Until such time as the Common Stock is
first registered under Section 12(g) of the 1934 Act, the Corporation shall have
the right of first refusal with respect to any proposed disposition by the
Optionee (or any successor in interest) of any shares of Common Stock issued
under the Plan. Such right of first refusal shall be exercisable in accordance
with the terms established by the Plan Administrator and set forth in the
document evidencing such right.

               G. LIMITED TRANSFERABILITY OF OPTIONS. During the lifetime of the
Optionee, the option shall be exercisable only by the Optionee and shall not be
assignable or transferable other than by will or by the laws of descent and
distribution following the Optionee's death. However, a Non-Statutory Option may
be assigned in whole or in part during Optionee's lifetime in accordance with
the terms of a Qualified Domestic Relations Order. The assigned portion may only
be exercised by the person or persons who acquire a proprietary interest in the
option pursuant to such Qualified Domestic Relations Order. The terms applicable
to the assigned portion shall be the same as those in effect for the option
immediately prior to such assignment and shall be set forth in such documents
issued to the assignee as the Plan Administrator may deem appropriate.

               H. WITHHOLDING. The Corporation's obligation to deliver shares of
Common Stock upon the exercise of any options granted under the Plan shall be
subject to the satisfaction of all applicable Federal, state and local income
and employment tax withholding requirements.

         II.   INCENTIVE OPTIONS

               The terms specified below shall be applicable to all Incentive
Options. Except as modified by the provisions of this Section II, all the
provisions of the Plan shall be applicable to Incentive Options. Options which
are specifically designated as Non-Statutory Options shall not be subject to the
terms of Section II.

               A. ELIGIBILITY. Incentive Options may only be granted to
Employees.

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               B. EXERCISE PRICE. The exercise price per share shall not be less
than one hundred percent (100%) of the Fair Market Value per share of Common
Stock on the option grant date.

               C. DOLLAR LIMITATION. The aggregate Fair Market Value of the
shares of Common Stock (determined as of the respective date or dates of grant)
for which one or more options granted to any Employee under the Plan (or any
other option plan of the Corporation or any Parent or Subsidiary) may for the
first time become exercisable as Incentive Options during any one (1) calendar
year shall not exceed the sum of One Hundred Thousand Dollars ($100,000). To the
extent the Employee holds two (2) or more such options which become exercisable
for the first time in the same calendar year, the foregoing limitation on the
exercisability of such options as Incentive Options shall be applied on the
basis of the order in which such options are granted.

               D. 10% STOCKHOLDER. If any Employee to whom an Incentive Option
is granted is a 10% Stockholder, then the option term shall not exceed five (5)
years measured from the option grant date.

         III.  CORPORATE TRANSACTION

               A. In the event of any Corporate Transaction, each outstanding
option shall terminate and cease to be outstanding, except to the extent assumed
by the successor corporation (or parent thereof) in connection with such
Corporate Transaction. In addition, all outstanding repurchase rights shall
terminate automatically in the event of any Corporate Transaction, except to the
extent the repurchase rights are assigned to the successor corporation (or
parent thereof) in connection with such Corporate Transaction.

               B. Each option which is assumed in connection with a Corporate
Transaction shall be appropriately adjusted, immediately after such Corporate
Transaction, to apply to the number and class of securities which would have
been issuable to the Optionee in the consummation of such Corporate Transaction,
had the option been exercised immediately prior to such Corporate Transaction.
Appropriate adjustments shall also be made to (i) the number and class of
securities available for issuance under the Plan following the consummation of
such Corporate Transaction and (ii) the exercise price payable per share under
each outstanding option, provided the aggregate exercise price payable for such
securities shall remain the same.

               C. The grant of options under the Plan shall in no way affect the
right of the Corporation to adjust, reclassify, reorganize or otherwise change
its capital or business structure or to merge, consolidate, dissolve, liquidate
or sell or transfer all or any part of its business or assets.

         IV.   CANCELLATION AND REGRANT OF OPTIONS

               The Plan Administrator shall have the authority to effect, at any
time and from time to time, with the consent of the affected option holders, the
cancellation of any or all outstanding options under the Plan and to grant in
substitution therefor new options covering the same or


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different number of shares of Common Stock but with an exercise price per share
based on the Fair Market Value per share of Common Stock on the new option grant
date.

                                  ARTICLE THREE

                                  MISCELLANEOUS


       I.      FINANCING

               The Plan Administrator may permit any Optionee to pay the option
exercise price by delivering a promissory note payable in one or more
installments. The terms of any such promissory note (including the interest rate
and the terms of repayment) shall be established by the Plan Administrator in
its sole discretion. Promissory notes may be authorized with or without security
or collateral. In all events, the maximum credit available to the Optionee may
not exceed the sum of (i) the aggregate option exercise price payable for the
purchased shares (less the par value of such shares) plus (ii) any Federal,
state and local income and employment tax liability incurred by the Optionee in
connection with the option exercise.

         II.   ADDITIONAL AUTHORITY

               A. The Plan Administrator shall have the discretion, exercisable
either at the time an option is granted or at any time while the option remains
outstanding, to extend the period of time for which the option is to remain
exercisable following the Optionee's cessation of Service or death from the
limited period otherwise in effect for that option to such greater period of
time as the Plan Administrator shall deem appropriate, but in no event beyond
the expiration of the option term.

     III.      EFFECTIVE DATE AND TERM OF THE PLAN

               A. The Plan shall become effective when adopted by the Board, but
no option granted under the Plan may be exercised until the Plan is approved by
the Corporation's stockholders. If such stockholder approval is not obtained
within twelve (12) months after the date of the Board's adoption of the Plan,
then all options previously granted under the Plan shall terminate and cease to
be outstanding, and no further options shall be granted. Subject to such
limitation, the Plan Administrator may grant options under the Plan at any time
after the effective date of the Plan and before the date fixed herein for
termination of the Plan.

               B. The Plan shall terminate upon the earliest of (i) the
expiration of the ten (10)-year period measured from the date the Plan is
adopted by the Board, (ii) the date on which all shares available for issuance
under the Plan shall have been issued or (iii) the termination of all
outstanding options in connection with a Corporate Transaction. Upon such Plan
termination, all options and unvested stock issuances outstanding under the Plan
shall continue to have full force and effect in accordance with the provisions
of the documents evidencing such options or issuances.

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         IV.   AMENDMENT OF THE PLAN

               A. The Board shall have complete and exclusive power and
authority to amend or modify the Plan in any or all respects. However, no such
amendment or modification shall, without the consent of the Optionees, adversely
affect their rights and obligations under their outstanding options. In
addition, the Board shall not, without the approval of the Corporation's
stockholders, (i) increase the maximum number of shares issuable under the Plan,
except for permissible adjustments in the event of certain changes in the
Corporation's capitalization, (ii) materially modify the eligibility
requirements for Plan participation or (iii) materially increase the benefits
accruing to Plan participants.

               B. Options may be granted under the Plan to purchase shares of
Common Stock in excess of the number of shares then available for issuance under
the Plan, provided any such options actually granted may not be exercised until
there is obtained stockholder approval of an amendment sufficiently increasing
the number of shares of Common Stock available for issuance under the Plan. If
such stockholder approval is not obtained within twelve (12) months after the
date the excess grants are first made, then any options granted on the basis of
such excess shares shall terminate and cease to be outstanding.

         V.    USE OF PROCEEDS

               Any cash proceeds received by the Corporation from the sale of
shares of Common Stock under the Plan shall be used for general corporate
purposes.

         VI.   REGULATORY APPROVALS

               The implementation of the Plan, the granting of any options under
the Plan and the issuance of any shares of Common Stock upon the exercise of any
option shall be subject to the Corporation's procurement of all approvals and
permits required by regulatory authorities having jurisdiction over the Plan,
the options granted under it and the shares of Common Stock issued pursuant to
it.


         VII.  NO EMPLOYMENT OR SERVICE RIGHTS

               Nothing in the Plan shall confer upon the Optionee any right to
continue in Service for any period of specific duration or interfere with or
otherwise restrict in any way the rights of the Corporation (or any Parent or
Subsidiary employing or retaining Optionee) or of the Optionee, which rights are
hereby expressly reserved by each, to terminate the Optionee's Service at any
time for any reason, with or without cause.

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         VIII. FINANCIAL REPORTS

               The Corporation shall deliver a balance sheet and an income
statement at least annually to each individual holding an outstanding option
under the Plan, unless such individual is a key Employee whose duties in
connection with the Corporation (or any Parent or Subsidiary) assure such
individual access to equivalent information.

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                                    APPENDIX


               The following definitions shall be in effect under the Plan:

         A. BOARD shall mean the Corporation's Board of Directors.

         B. CODE shall mean the Internal Revenue Code of 1986, as amended.

         C. COMMITTEE shall mean a committee of two (2) or more Board members
appointed by the Board to exercise one or more administrative functions under
the Plan.

         D. COMMON STOCK shall mean the Corporation's common stock.

         E. CORPORATE TRANSACTION shall mean either of the following
stockholder-approved transactions to which the Corporation is a party:

                   (i) a merger or consolidation in which securities possessing
         more than fifty percent (50%) of the total combined voting power of the
         Corporation's outstanding securities are transferred to a person or
         persons different from the persons holding those securities immediately
         prior to such transaction, or

                  (ii) the sale, transfer or other disposition of all or
         substantially all of the Corporation's assets in complete liquidation
         or dissolution of the Corporation.

         F. CORPORATION shall mean Model Corporation, Inc., a Delaware
corporation.

         G. DISABILITY shall mean the inability of the Optionee to engage in any
substantial gainful activity by reason of any medically determinable physical or
mental impairment and shall be determined by the Plan Administrator on the basis
of such medical evidence as the Plan Administrator deems warranted under the
circumstances. Disability shall be deemed to constitute PERMANENT DISABILITY in
the event that such Disability is expected to result in death or has lasted or
can be expected to last for a continuous period of twelve (12) months or more.

         H. DOMESTIC RELATIONS ORDER shall mean any judgment, decree or order
(including approval of a property settlement agreement) which provides or
otherwise conveys, pursuant to applicable State domestic relations laws
(including community property laws), marital property rights to any spouse or
former spouse of the Optionee.

         I. EMPLOYEE shall mean an individual who is in the employ of the
Corporation (or any Parent or Subsidiary), subject to the control and direction
of the employer entity as to both the work to be performed and the manner and
method of performance.



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         J. EXERCISE DATE shall mean the date on which the Corporation shall
have received written notice of the option exercise.

         K. FAIR MARKET VALUE per share of Common Stock on any relevant date
shall be determined in accordance with the following provisions:

                   (i) If the Common Stock is at the time traded on the Nasdaq
         National Market, then the Fair Market Value shall be the closing
         selling price per share of Common Stock on the date in question, as
         such price is reported by the National Association of Securities
         Dealers on the Nasdaq National Market or any successor system. If there
         is no closing selling price for the Common Stock on the date in
         question, then the Fair Market Value shall be the closing selling price
         on the last preceding date for which such quotation exists.

                  (ii) If the Common Stock is at the time listed on any Stock
         Exchange, then the Fair Market Value shall be the closing selling price
         per share of Common Stock on the date in question on the Stock Exchange
         determined by the Plan Administrator to be the primary market for the
         Common Stock, as such price is officially quoted in the composite tape
         of transactions on such exchange. If there is no closing selling price
         for the Common Stock on the date in question, then the Fair Market
         Value shall be the closing selling price on the last preceding date for
         which such quotation exists.

                 (iii) If the Common Stock is at the time neither listed on any
         Stock Exchange nor traded on the Nasdaq National Market, then the Fair
         Market Value shall be determined by the Plan Administrator after taking
         into account such factors as the Plan Administrator shall deem
         appropriate.

         L. HIGHLY-COMPENSATED EMPLOYEE shall mean an Optionee (i) whose
compensation per calendar year from the Corporation (or any Parent or
Subsidiary) equals or exceeds Sixty Thousand Dollars ($60,000) in the aggregate
and (ii) who has previously received one or more option grants under the Plan.

         M. INCENTIVE OPTION shall mean an option which satisfies the
requirements of Code Section 422.

         N. 1934 ACT shall mean the Securities Exchange Act of 1934, as amended.

         O. NON-STATUTORY OPTION shall mean an option not intended to satisfy
the requirements of Code Section 422.

         P. OPTIONEE shall mean any person to whom an option is granted under
the Plan.



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         Q. PARENT shall mean any corporation (other than the Corporation) in an
unbroken chain of corporations ending with the Corporation, provided each
corporation in the unbroken chain (other than the Corporation) owns, at the time
of the determination, stock possessing fifty percent (50%) or more of the total
combined voting power of all classes of stock in one of the other corporations
in such chain.

         R. PLAN shall mean the Corporation's 1995 Stock Option Plan, as set
forth in this document.

         S. PLAN ADMINISTRATOR shall mean either the Board or the Committee, to
the extent the Committee is at the time responsible for the administration of
the Plan.

         T. QUALIFIED DOMESTIC RELATIONS ORDER shall mean a Domestic Relations
Order which substantially complies with the requirements of Code Section 414(p).
The Plan Administrator shall have the sole discretion to determine whether a
Domestic Relations Order is a Qualified Domestic Relations Order.

         U. SERVICE shall mean the provision of services to the Corporation (or
any Parent or Subsidiary) by a person in the capacity of an Employee, a
non-employee member of the board of directors or a consultant, except to the
extent otherwise specifically provided in the documents evidencing the option
grant.

         V. STOCK EXCHANGE shall mean either the American Stock Exchange or the
New York Stock Exchange.

         W. SUBSIDIARY shall mean any corporation (other than the Corporation)
in an unbroken chain of corporations beginning with the Corporation, provided
each corporation (other than the last corporation) in the unbroken chain owns,
at the time of the determination, stock possessing fifty percent (50%) or more
of the total combined voting power of all classes of stock in one of the other
corporations in such chain.

         X. 10% STOCKHOLDER shall mean the owner of stock (as determined under
Code Section 424(d)) possessing more than ten percent (10%) of the total
combined voting power of all classes of stock of the Corporation (or any Parent
or Subsidiary).






