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                                                                    EXHIBIT 10.8


                       MASTER EQUIPMENT LEASE AGREEMENT
                    Agreement No. 203 Dated: April 28, 1998


LESSOR:    LIGHTHOUSE CAPITAL PARTNERS II, L.P., a Delaware limited partnership
           ("Lessor"), 100 Drakes Landing Road, Suite 260, Greenbrae, California
           94904-3121

LESSEE:    CRITICAL PATH, INC., a California corporation ("Lessee")

ADDRESS:   320 First Street, San Francisco, California 94105.

     IN CONSIDERATION of the mutual covenants contained herein, the parties
agree as follows:

     1.  LEASE.  Lessor leases to Lessee and Lessee leases from Lessor the
personal property described in each Equipment Schedule executed pursuant hereto,
subject to the terms and conditions of this Master Equipment Lease Agreement
("Master Lease") and the applicable Lease Line Schedule (defined below).  The
"Equipment" (as defined in the Lease Line Schedule) is being leased for
commercial or business purposes only, and not for personal, home, or family
purposes.  The parties agree that each Lease is a "finance lease" under the
Uniform Commercial Code (as in effect in the State of California during the term
of the Lease and referred to hereafter as the "UCC").

     2.  LEASE LINE SCHEDULE.  "Lease Line Schedule" means a Lease Line Schedule
in the form of Exhibit A, signed by Lessor and Lessee and incorporating by
reference the terms and provisions of this Master Lease.

     3.  EQUIPMENT SCHEDULES.  "Equipment Schedule" means an Equipment Schedule
in the form of Exhibit B, signed by Lessor and Lessee and incorporating, by
reference, the terms and provisions of this Master Lease and the applicable
Lease Line Schedule.  Each Equipment Schedule shall constitute a separate and
independent lease (a "Lease"); the original of such Lease shall consist of the
signed Equipment Schedule and a copy of the Master Lease and applicable Lease
Line Schedule.  Capitalized terms used, but not defined, in this Master Lease
have the meanings given to such terms in the applicable Lease Line Schedule or
Equipment Schedule, as the case may be.

     4.  TERM AND RENTALS.

              (a)  Acceptance.  The Lease shall commence with respect to
Equipment described on the Equipment Schedule upon the Acceptance Date. The
"Acceptance Date" shall be the date upon which Lessee executes a Delivery and
Acceptance Certificate in the form of Exhibit C.

              (b)  Term and Payment of Rent.  The lease term for the Equipment
shall be the "Lease Term" set forth in the Equipment Schedule which shall
commence on the "Commencement Date" (as defined in the Lease Line Schedule).
Lessee agrees to pay to Lessor the "Rental Payments" for the Lease Term, in the
amounts and at the times set forth in the Equipment Schedule.

              (c)  Lease Termination.  Lessee may terminate the Lease at the
expiration of the Lease Term or any renewal term (the "Lease Termination") by
submitting to Lessor a Notice of Election in the form of Exhibit D. If a Notice
of Election is not submitted by Lessee to Lessor during the "Advance Notice
Period" (as defined in the Lease Line Schedule), then the Lease Term or any
renewal Term will be automatically extended for an additional period equal to
the "Automatic Extension Period" (as defined in the Lease Line Schedule). The
Lease will continue to automatically extend until Lessee submits to Lessor a
Notice of Election. The Lease may only be terminated as expressly provided in
this Section, in the applicable Lease Line Schedule or in the applicable
Equipment Schedule. Lessee agrees to continue paying rent for the Equipment in
the amount of the Rental Payment set forth in the Equipment Schedule until the
later of (i) the expiration of the Lease Term, any renewal term and any
Automatic Extension Period and (ii) either (A) the purchase option price is paid
pursuant to Section 6(a), or (B) a mutually agreed renewal of the Lease takes
effect pursuant to Section 6(b), or (C) the Equipment is returned in the manner
and condition prescribed in Section 6(c), in each case after delivery of a
Notice of Election.

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              (e)  Net Lease.  Each Equipment Schedule shall be a net lease, and
Lessee's obligation to pay all rent and other sums thereunder shall be absolute
and unconditional, and shall not be subject to any abatement, reduction, set-
off, defense, counterclaims, interruption, deferment or recoupment, for any
reason whatsoever.

     5.  LATE FEE.  Lessee shall pay a late charge on any rent payments or other
sums due hereunder which are past due, in the amount specified in the Lease Line
Schedule, payable on demand.  In addition, interest shall accrue daily at the
"Default Rate" (as defined in the Lease Line Schedule), or if such rate exceeds
the maximum rate allowed by law, then at such maximum rate, and shall be payable
on demand.

     6. LEASE TERMINATION OPTIONS.  Upon Lease Termination, Lessee will have the
option to purchase the Equipment, renew the term of the Lease, or return the
Equipment to Lessor, as set forth below.  Lessee shall specify its election of a
Lease Termination Option in the Notice of Election.

              (a)  Purchase Option.  If Lessee exercises the option to purchase,
then, provided no Event of Default has occurred and is then continuing, Lessee
shall at the expiration of the Lease Term, renewal term or extension, as the
case may be, purchase the Equipment. The purchase price shall be the Equipment's
then fair market value ("FMV"). FMV, as applied to a purchase option, shall be
determined by Lessor based on the price a willing buyer would pay and a willing
seller would accept (neither buyer nor seller being under compulsion to act) for
the Equipment as installed and in use, giving due consideration to its
condition, utility, revenue-producing capability, and replacement costs. If
Lessee fails to agree with Lessor's good faith determination of the FMV, Lessee
shall nevertheless pay Lessor's invoice and provide Lessor with a written
request for a determination of the FMV with or prior to such payment. Within ten
(10) days after such request Lessor and Lessee shall agree on an appraiser to
determine the FMV or, lacking such agreement, shall each tender the name of an
appraiser. The appraiser(s) shall, within thirty (30) days, either agree on the
FMV or select a third appraiser, to form a committee to determine the FMV.
Determination by the appraiser(s) shall be final and binding on both parties.
Within fifteen (15) days after such determination, Lessor shall refund any
excess received over the FMV, and/or Lessee shall pay any additional amount of
the FMV above the amount previously paid. Each party shall bear the fees and
expenses of any appraiser which it names and share equally the fees and expenses
of any appraiser(s) jointly selected. If the appraised FMV is within 5% of the
amount invoiced by Lessor, then Lessee shall pay all appraiser fees and
expenses. The purchase option price shall be paid not later than the last day of
the Lease Term.

              (b)  Renewal.  If Lessee exercises the option to renew this Lease,
such renewal shall be upon the terms and conditions of this Master Lease and the
applicable Lease Line Schedule, for a rental period and rental amount to be
agreed upon by Lessee and Lessor.

              (c)  Return.  If the Notice of Election specifies return of the
Equipment, Lessee at its own risk and expense (i) will immediately return the
Equipment to Lessor in the same condition as when delivered, ordinary wear and
tear excepted, at such location as Lessor shall designate; and (ii) will, on
request from Lessor, obtain from the Equipment supplier (or other maintenance
service supplier approved by Lessor) a certificate stating that the Equipment
qualifies for continued maintenance service at the standard rates and terms then
in effect.

     7.  USE; MAINTENANCE.

              (a)  Lessee, at its expense, shall make all necessary site
preparations and cause the Equipment to be operated in accordance with any
applicable operating manuals and manufacturer's instructions. Notwithstanding
any transfer or assignment by Lessor and provided Lessee is not in default
hereunder, Lessee shall have the right to quietly possess and use the Equipment
as provided herein without interference by Lessor, its assigns or any other
third party claiming through or under Lessor.

              (b)  Lessee shall effect and bear the expense of all necessary
repair, maintenance, operation and replacements required to be made to maintain
the Equipment in good condition, reasonable wear and tear excepted, and to
comply with all domestic and international laws to which the use and operation
of the Equipment may be or become subject. All replacement Equipment and parts
furnished in connection with such maintenance or repair shall immediately become
the property of Lessor and part of the Equipment for all purposes hereof. All
such 

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maintenance, repair and replacement services shall be immediately paid for and
discharged by Lessee with the result that no lien under any applicable laws will
attach to the Equipment as a result of the performance of such services or the
provision of any such material.

     8.  INSURANCE.  Lessee shall obtain and maintain for the Lease Term (and
any renewal term or extension), at its own expense, (a) "all risk" insurance
against loss or damage to the Equipment, (b) commercial general liability
insurance (including contractual liability, products liability and completed
operations coverage) reasonably satisfactory to Lessor, and (c) such other
insurance against such other risks of loss and with such terms, as shall in each
case be reasonably satisfactory to or reasonably required by Lessor (as to
carriers, amounts and otherwise).  The amount of the "all risk" insurance shall
be greater than or equal to the Stipulated Loss Value (as defined in Section 9
below) of all Equipment outstanding under the Lease Line Schedule, and must
otherwise be reasonably satisfactory to Lessor as of each anniversary date of
this Lease.  Any increase in the amount of such insurance coverage, other than
"all risk", reasonably requested by Lessor shall be put into effect on the next
succeeding renewal date of such insurance.

     Each "all risk" policy shall:  (i) name Lessor as sole loss payee with
respect to the Equipment, (ii) provide for each insurer's waiver of its right of
subrogation against Lessor and Lessee, and (iii) provide that such insurance
shall not be invalidated by any action of, or breach of warranty by, Lessee of a
provision of any of its insurance policies, and shall waive set-off,
counterclaim or offset against Lessor.

     Each liability policy shall name Lessor as an additional insured and
provide that such insurance shall have cross-liability and severability of
interest endorsements (which shall not increase the aggregate policy limits of
Lessee's insurance).

     All insurance policies shall provide that Lessee's insurance shall be
primary without a right of contribution of Lessor's insurance, if any, or any
obligation on the part of Lessor to pay premiums of Lessee, and shall contain a
clause requiring the insurer to give Lessor at least 30 days' prior written
notice of its cancellation (other than cancellation for non-payment for which 10
days' notice shall be sufficient).  Lessee shall on or prior to the date of
Equipment Schedule No. 01 and prior to each policy renewal, furnish to Lessor
certificates of insurance or other evidence satisfactory to Lessor that such
insurance coverage is in effect.  Lessee further agrees to give Lessor prompt
notice of any damage to, or loss of, the Equipment, or any part thereof.

     9.  LOSS OR DAMAGE.  If any items of Equipment shall become lost, stolen,
destroyed, or damaged beyond repair for any reason, or in the event of
condemnation, confiscation, seizure or requisition of title to or use of such
items (collectively, an "Event of Loss"), Lessee shall promptly pay to Lessor
the applicable Stipulated Loss Value of the Equipment subject to the Event of
Loss.  Upon payment by Lessee of the Stipulated Loss Value, Lessor will transfer
to Lessee, "AS IS, WHERE IS, WITHOUT RECOURSE, REPRESENTATION OR WARRANTY," all
of Lessor's right, title and interest, if any, in such items of Equipment.  The
"Stipulated Loss Value" payable by Lessee under this Lease shall be an amount
equal to the product of (a) Lessor's Cost of the affected Equipment and (b) the
percentage set forth in the table attached to the applicable Lease Line Schedule
as Annex A opposite the Rental Payment number next following the Event of Loss.
Stipulated Loss Values and Rental Payments shall not be prorated.

     10.  TITLE, INSPECTION AND LOCATION.

              (a)  Title.  Lessor and Lessee confirm their intent that title to
the Equipment shall remain in Lessor (or its successors and assigns)
exclusively. If requested by Lessor, Lessee will affix plates or markings on the
Equipment and on any operating manuals and manufacturer's instructions
indicating the interests of Lessor and its assigns therein, and Lessee will not
allow any other indicia of ownership or other interest in the Equipment to be
placed on the Equipment. Lessee shall not sell, assign, grant a security
interest in, sublet, pledge, hypothecate or otherwise encumber or suffer a lien
upon or against this Lease or the Equipment.

              (b)  Inspection.  Lessor (through any of its officers, employees
or agents) shall have the right to inspect the Equipment during regular business
hours, with reasonable notice, and in compliance with Lessee's reasonable
security procedures; provided, that such inspections will be conducted no more
often then once every six 

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(6) months unless an Event of Default, or event which, with notice or lapse of
time or both, would become an Event of Default, has occurred and is continuing.

              (c)  Location.  In the case of Equipment other than mobile
Equipment, Lessee may move such Equipment from the installation address shown on
the Equipment Schedule (or any other location for which Lessee has complied with
this provision) only if (i) the new location is within the continental United
                ----                                                         
States, and (ii) Lessee gives at least 30 days' prior written notice of the
relocation and provides UCC-1 financing statements, landlord waivers or such
other documentation as Lessor reasonably requests to protect its interest in the
Equipment.  In the case of mobile equipment (including, without limitation, lap-
top computers), Lessee agrees to obtain from the person using such mobile
Equipment and deliver to Lessor, an Acknowledgment in the form of Exhibit F.

              (d)  Lessee shall keep copies of all operating manuals and
manufacturer's instructions with respect to the Equipment in good condition at
the locations specified in Section 10(c).

     11.  LESSEE'S REPRESENTATIONS, WARRANTIES AND WAIVERS.  Upon execution of
the Master Lease and each Equipment Schedule, Lessee warrants and represents the
following:

              (a)  Lessee is a corporation duly organized, validly existing and
in good standing under the laws of its state of incorporation. Lessee has full
power and authority and all necessary licenses and permits to carry on its
business as presently conducted, to own or hold under lease its properties and
to enter into this Master Lease, the Lease Line Schedule and each Equipment
Schedule and to perform its obligations thereunder; and Lessee is duly qualified
to do business as a foreign corporation and is in good standing in each
jurisdiction in which the character of its properties or the nature of its
business or the performance of its obligations under this Master Lease, the
Lease Line Schedule and any Equipment Schedule requires such qualification,
except for such jurisdictions in which failure to qualify would not have a
material adverse effect on Lessee.

              (b)  The execution and delivery by Lessee of this Master Lease,
the Lease Line Schedule and each Equipment Schedule and the performance by
Lessee of its obligations thereunder have been duly authorized by all necessary
corporate action on the part of Lessee; and do not and will not contravene the
provisions of, or constitute a default (either with or without notice or lapse
of time, or both) under, or result in the creation of any lien upon, the
Equipment or any property of Lessee under any indenture, mortgage, contract or
other instrument to which Lessee is a party or by which Lessee or its properties
is bound.

              (c)  No consent or approval of, giving of notice to, registration
with, or taking of any other action by, any state, federal, foreign or other
governmental commission, agency or regulatory authority or any other person or
entity is required for the consummation or performance by Lessee of the
transactions contemplated under this Master Lease, the Lease Line Schedule and
each Equipment Schedule.

              (d)  This Master Lease, the Lease Line Schedule and each Equipment
Schedule, when executed by Lessee, constitute legal, valid and binding
agreements of Lessee enforceable against Lessee in accordance with their terms,
except as limited by any bankruptcy, insolvency, reorganization, or other
similar laws of general application affecting the enforcement of creditor or
Lessor rights.

              (e)  There are no actions, suits or proceedings pending or
threatened against or affecting Lessee or any property of Lessee in any court,
before any arbitrator of any kind or before or by any federal state, municipal
or other government department, commission, board, bureau, agency or
instrumentality (collectively "Governmental Body"), which, if adversely
determined, would materially adversely affect the business, financial condition,
assets, or operations of Lessee, or adversely affect the ability of Lessee to
perform its obligations under this Master Lease, the Lease Line Schedule and
each Equipment Schedule; and Lessee is not in default with respect to any order
of any court, arbitrator or Governmental Body or with respect to any material
loan agreement, debt instrument or contract with a supplier or customer of
Lessee, except as disclosed in writing to Lessor.

              (f)  To the extent permitted by applicable law, Lessee waives any
and all rights and remedies to: (i) cancel this Lease; (ii) repudiate this
Lease; (iii) reject the Equipment; (iv) revoke acceptance of the Equipment; (v)
recover damages from Lessor for any breaches of warranty or for any other
reason; (vi) claim a security interest 

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in the Equipment in Lessee's possession or control for any reason; (vii) deduct
from Rental Payments all or any part of any claimed damages resulting from
Lessor's default, if any, under this Lease; (viii) accept partial delivery of
the Equipment; (ix) "cover" by making any purchase or lease of or contract to
purchase or lease equipment in substitution for Equipment designated in the
Lease; (x) recover any direct, general, special, incidental, indirect, exemplary
or consequential damages, for any reason whatsoever; and (xi) obtain specific
performance, replevin, detinue, sequestration, claim and delivery or the like
for any Equipment identified to this Lease. To the extent permitted by
applicable law, Lessee also waives any rights now or hereafter conferred by
statute or otherwise which may require Lessor to sell, lease or otherwise use
any Equipment in mitigation of Lessor's damages or which may otherwise limit or
modify any of Lessor's rights or remedies.

     12.  ASSIGNMENT BY LESSOR.  LESSEE ACKNOWLEDGES THAT LESSOR MAY SELL,
ASSIGN, GRANT A SECURITY INTEREST IN, OR OTHERWISE TRANSFER ALL OR ANY PART OF
ITS RIGHTS, TITLE AND INTEREST IN THIS LEASE AND THE EQUIPMENT WITHOUT NOTICE TO
OR CONSENT OF LESSEE.  Upon Lessor's written notice to Lessee that this Lease,
or the right to the Rental Payments hereunder, have been assigned, Lessee shall,
if requested, pay directly to Lessor's assignee without abatement, deduction or
set-off all amounts which become due hereunder.  Lessee waives and agrees it
will not assert against Lessor's assignee any counterclaim or set-off in any
action for rent under the Lease.  Upon the assignment of this Lease, Lessor's
assignee shall have and be entitled to exercise any and all rights and remedies
(but none of the obligations) of Lessor hereunder, and all references herein to
Lessor shall include Lessor's assignee. Lessee acknowledges that any assignment
or transfer by Lessor does not materially change Lessee's duties or obligations
under this Lease nor materially increase the burdens or risks imposed on Lessee.

     13.  ASSIGNMENT BY LESSEE.  LESSEE MAY NOT, WITHOUT LESSOR'S PRIOR WRITTEN
CONSENT, (i) ASSIGN THIS LEASE, WHETHER BY OPERATION OF LAW OR OTHERWISE, OR
SUBLEASE THE EQUIPMENT OR ANY PART THEREOF OR (ii) ASSIGN, GRANT A SECURITY
INTEREST IN, OR  OTHERWISE TRANSFER ALL OR ANY PART OF ITS RIGHTS, TITLE AND
INTEREST IN AND TO THIS LEASE OR THE EQUIPMENT.  Notwithstanding the foregoing,
in the event of a merger, sale of substantially all of the assets or other
reorganization involving Lessee in which the shareholders of Lessee immediately
prior to such transaction own less than 50% of the voting securities of the
surviving entity or purchaser of assets (or its parent) in such transaction,
Lessor shall not withhold its consent to the assignment of this Lease to the
successor entity if each of the following conditions precedent is satisfied:

     (i) the successor entity as of the date of such assignment meets Lessor's
then current credit standards, as determined by Lessor in Lessor's sole
discretion;

     (ii) Lessee gives Lessor at least thirty (30) days prior written notice of
such merger, sale of assets or other reorganization;

     (iii) such merger, sale of assets or other reorganization does not
adversely affect the rights of Lessor;

     (iv) the corporation that results from such merger or other reorganization
or which purchases the assets in the case of a sale of assets (the "Surviving
Corporation") shall have executed and delivered to Lessor an agreement in form
and substance reasonably satisfactory to Lessor, containing an assumption by
Surviving Corporation of the due and punctual performance and observance of each
covenant and condition of Lessee in the Master Lease, Lease Line Schedule and
Equipment Schedules (the "Lease Documents") and making representations and
warranties with respect to the Surviving Corporation similar in scope and
substance to the representations and warranties made by Lessee in the Lease
Documents;

     (v) the Surviving Corporation executes any precautionary financing
statements or amendments thereto reasonably requested by Lessor; and

     (vi) immediately after giving effect of such merger, sale of assets or
other reorganization, no Event of Default or, event which with the lapse of time
or giving of notice or both, would result in an Event of Default shall have
occurred and be continuing.  In the event Lessee makes an assignment, sublease
or other transfer (to which 

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Lessor has consented), Lessee shall not thereby be relieved of its duties and
obligations hereunder, for which it shall remain fully responsible and liable
(independent of its assignee).

     14.  TAXES.

              (a)  Lessee shall comply with all applicable federal, state,
local, foreign and international laws, regulations and orders relating to this
Lease. Lessee assumes liability for, and shall pay when due, and on a net after-
tax basis shall indemnify and defend Lessor against, all federal, state, local,
foreign and international fees, taxes and government charges (including, without
limitation, interest and penalties) of any nature imposed upon or in any way
relating to Lessor, Lessee, any item of Equipment or this Lease, except federal,
state and local taxes on or measured by Lessor's net income (other than any such
tax which is in substitution for or relieves Lessee from the payment of taxes it
would otherwise be obligated to pay to or reimburse Lessor for as herein
provided). Lessee shall at its expense file when due with the appropriate
authorities any and all tax and similar returns and reports required to be filed
with respect thereto or, if requested by Lessor, notify Lessor of all such
requirements and furnish Lessor with all information required for Lessor to
effect such filings, which filings shall also be at Lessee's expense. Any fees,
taxes or other charges paid by Lessor upon failure of Lessee to make such
payments shall at Lessor's option become immediately due from Lessee to Lessor.

              (b)  This Lease has been entered into on the assumption that
Lessor shall be entitled to all deductions, credits, and other tax benefits as
are provided in the Internal Revenue Code of 1986, including amendments as may
occur (the "Code"), to an owner of property including, without limitation,
depreciation deductions and interest deductions with respect to any debts
incurred to finance the purchase of the Equipment. If, as a result of any acts,
omissions or misrepresentations by Lessee Lessor's projected after-tax economic
return resulting from ownership and lease of the Equipment is reduced, then
Lessee's Rental Payments shall be increased in an amount (based on Lessor's
reasonable calculations) sufficient to provide the same net after-tax economic
return as if such acts or omissions or changes had not occurred. Appropriate
increases shall also be made in the applicable Stipulated Loss Values for this
Lease.

     15.  EQUIPMENT WARRANTIES.  Lessee acknowledges that (i) Lessee has
selected the supplier of the Equipment, (ii) Lessor acquired the goods or the
right to possession and use of the goods in connection with the Lease, and (iii)
Lessee received a copy of the contract by which Lessor acquired the Equipment or
the right to possession and use of the Equipment before signing the Lease.
LESSOR MAKES NO EXPRESS OR IMPLIED WARRANTIES INCLUDING THOSE OF MERCHANTABILITY
OR FITNESS FOR A PARTICULAR USE WITH RESPECT TO THE EQUIPMENT AND DISCLAIMS THE
SAME.  Lessor shall have no liability for any damages, whether direct, indirect,
general, special, incidental, exemplary or consequential, incurred by Lessee as
a result of any defect or malfunction of the Equipment.  Lessee shall look
solely to the Equipment supplier for any and all claims related to the
Equipment.  Lessor assigns to Lessee, for and during the Lease Term, any
warranty on the Equipment provided by the supplier, provided, that to the extent
that they are not assignable, Lessor shall, at Lessee's sole expense, take all
reasonable action to enforce any warranty on the Equipment..  Lessor and Lessee
agree that all limitations on remedies and liability contained in this Lease
represent a reasonable allocation of risks that is part of the fundamental
bargain between the parties.

     16.  EVENTS OF DEFAULT.  An Event of Default shall occur if Lessee (i)
fails to pay any Rental Payment or other payment required under the Lease when
due and such failure continues for a period of five (5) days after written
notice from Lessor; or (ii) fails to perform or observe any other covenant,
condition or agreement to be performed or observed by it or breaches any
provision contained in the Lease or in any other document furnished to Lessor in
connection herewith, and such failure or breach continues for a period of thirty
(30) days after written notice from Lessor; or (iii) without Lessor's consent,
attempts to assign this Lease or sell, transfer, encumber, part with possession,
or sublet any item of Equipment; or (iv) makes any representation or warranty
herein or in any document furnished by Lessee in connection herewith, which
shall have been materially false or inaccurate when made or at the time to which
such representation or warranty relates; or (v) shall commit an act of
bankruptcy or become insolvent or bankrupt or make an assignment for the benefit
of creditors or consent to the appointment of a Trustee or Receiver or either
shall be appointed for Lessee or for a substantial part of its property without
its consent, or bankruptcy reorganization, or insolvency proceedings shall be
instituted by or against Lessee, and, if instituted against Lessee, shall not be
vacated or dismissed within sixty (60) days.  Any Event of Default shall be

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deemed material and a substantial impairment of Lessor's interests for the
purposes of this Lease, the UCC, and any other applicable law.

     17.  REMEDIES.  Upon the occurrences of any Events of Default and at any
time thereafter, provided such Event of Default is then continuing, Lessor may,
in its discretion, do any one or more of the following:

              (a)  cancel any or all Leases which reference this Master Lease or
the Lease Line Schedule, upon notice to Lessee;

              (b)  recover any accrued and unpaid Rental Payments and other
amounts which are due and owing under the Leases so canceled on the Rental
Payment Date immediately preceding the date on which Lessor obtains possession
of the Equipment (or such earlier date as judgment is entered in favor of
Lessor) (the "Determination Date"), plus interest at the Default Rate;

              (c)  with or without canceling this Lease, recover (i) such
Stipulated Loss Value as of the Rental Payment Date immediately preceding the
Determination Date, and (ii) the amount of any loss or reduction of tax benefits
which Lessor anticipated it would receive if the Lease continued for its full
Lease Term;

              (d)  recover any amounts due under any indemnity then
determinable, plus interest at the Default Rate;

              (e)  require that Lessee provide the return and certification of
the Equipment in accordance with Section 6(c) hereof;

              (f)  enter the premises where such Equipment is located and take
immediate possession of and remove the same, all without liability to Lessor or
its agents for such entry;

              (g)  sell any or all of the Equipment at public or private sale,
with or without notice to Lessee or advertisement, or otherwise dispose of,
hold, use, operate, lease to others or keep idle such Equipment, all free and
clear of any rights of Lessee and without any duty to account to Lessee for such
action or inaction or for any proceeds with respect thereto; and

              (h)  exercise any other right or remedy which may be available to
it under the UCC or other applicable law including the right to recover damages
for the breach hereof.

     In addition, Lessee shall be liable for, and reimburse Lessor for, all
reasonable legal fees and all commercially reasonable costs and expenses
incurred by Lessor as a result of the foregoing defaults or the exercise of
Lessor's remedies, including without limitation recovering possession of the
Equipment, selling or leasing the Equipment (including broker's and sales
representative's fees and commissions), and placing any Equipment in the
condition and obtaining the certificate required by Section 6(c) hereof.  No
remedy referred to in this Section is intended to be exclusive, but each shall
be cumulative and in addition to any other remedy referred to above or otherwise
available to Lessor at law or in equity.  No express or implied waiver by Lessor
of any default shall constitute a waiver of any other default by Lessor, or a
waiver of any of Lessor's rights.

     18.  INDEMNIFICATION.  Lessee assumes liability for, and shall pay when
due, and shall indemnify, reimburse and hold each Indemnified Person (defined
below) harmless from and against all Claims (defined below), directly or
indirectly relating to or arising out of the acquisition, use, manufacture,
purchase, shipment, transportation, delivery, installation, lease or sublease,
ownership, operation, possession, control, storage, return or condition of any
item of Equipment (regardless of whether such item of Equipment is at the time
in the possession of Lessee), the falsity of any non-tax representation or
warranty of Lessee or Lessee's failure to comply with the terms of the Lease
during the Lease Term.  The foregoing indemnity shall cover, without limitation,
(i) any Claim in connection with a design or other defect (latent or patent) in
any item of Equipment, (ii) any Claim for infringement of any patent, copyright,
trademark or other intellectual property right, or (iii) any Claim for
negligence or strict or absolute liability in tort; provided, however, that
Lessee shall not indemnify Lessor for any liability incurred by Lessor as a
direct and sole result of Lessor's gross negligence or willful misconduct.

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     "Claim" means all liabilities, losses, damages, actions, suits, demands,
claims of any kind and nature (including, without limitation, claims relating to
environmental discharge, cleanup or compliance), and all costs and expenses
whatsoever to the extent they may be incurred or suffered by an Indemnified
Person in connection therewith (including, without limitation, reasonable
attorneys' fees and expenses), fines, penalties (and other charges of applicable
governmental authorities), licensing fees relating to any item of Equipment,
damage to or loss of use of property (including, without limitation,
consequential or special damages to third parties or damages to Lessee's
property), or bodily injury to or death of any person (including, without
limitation, any agent or employee of Lessee).

     "Indemnified Person" means Lessor (including without limitation, each of
its partners) and each of their respective successors, assigns, agents,
officers, directors, shareholders, partners, servants, agents and employees.
 
     Such indemnities shall continue in full force and effect, notwithstanding
the expiration or termination of this Lease.  Upon Lessor's written demand,
Lessee shall assume and diligently conduct, at its sole cost and expense, the
entire defense of any Indemnified Person against any indemnified Claim described
in this Section 18.  Lessee shall not settle or compromise any Claim against or
involving Lessor without first obtaining Lessor's written consent thereto, which
consent shall not be unreasonably withheld.  Lessee shall give Lessor prompt
notice of any occurrence, event or condition in connection with which Lessor may
be entitled to indemnification hereunder.  The provisions of this Section 18 are
in addition to, and not in limitation of, the provisions of Section 14(b).

     19.  NOTICES.  Any notices or demands required or permitted hereunder shall
be given to the parties in writing and by personal delivery, regular or
certified mail, facsimile or telegram at the address set forth in the Lease Line
Schedule or to such other address as the parties may hereafter substitute by
written notice given in the manner prescribed in this Section.  Such notices or
demands shall be deemed given upon receipt in the case of personal delivery and
upon mailing or transmission in the case of mail, facsimile or telegram.  Lessee
agrees to provide Lessor with thirty (30) days' prior written notice of (a) any
merger or consolidation with or into any other business organization, (b) any
sale, lease or other disposition of assets not in the ordinary course of
business, and (c) any other material change in Lessee's financial structure or
ownership.

     20.  FURTHER ASSURANCES.  Lessee will promptly execute and deliver to
Lessor such further reasonable documents and take such further reasonable action
as Lessor may request in order to more effectively carry out the intent and
purpose of this Lease or an assignment of Lessor's interest herein.

     21.  MISCELLANEOUS.  This Lease shall be binding upon and inure to the
benefit of the parties hereto, their permitted successors and assigns.  Any
provision of the Lease which is unenforceable in any jurisdiction shall, as to
such jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions hereof; and any
such prohibition or unenforceability in any jurisdiction shall not invalidate or
render unenforceable such provision in any other jurisdiction; provided,
however, that to the extent that the provisions of any such applicable law can
be waived, they are waived by Lessee.  Time is of the essence with respect to
the Lease.  The captions set forth herein are for convenience only and shall not
define or limit any of the terms hereof.  THIS LEASE SHALL IN ALL RESPECTS BE
GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF
CALIFORNIA, WITHOUT REFERENCE TO CONFLICT OF LAWS PRINCIPLES.  LESSOR AND LESSEE
WAIVE ALL RIGHTS TO TRIAL BY JURY IN ANY LITIGATION ARISING FROM THIS LEASE.
THIS LEASE SHALL BECOME EFFECTIVE AND BINDING ON THE PARTIES, THEIR RESPECTIVE
SUCCESSORS AND PERMITTED ASSIGNS, AND SHALL BE DEEMED EXECUTED AND PERFORMED IN
THE STATE OF CALIFORNIA, WHEN THE RELATED EQUIPMENT SCHEDULE IS ACCEPTED BY
LESSOR.  LESSEE CONSENTS TO THE NON-EXCLUSIVE JURISDICTION OF THE STATE COURTS
OF CALIFORNIA FOR THE RESOLUTION OF ANY DISPUTES HEREUNDER.

                                       8
<PAGE>
 
     22.  AMENDMENTS, MODIFICATIONS, WAIVERS.  NONE OF THE PROVISIONS OF THIS
LEASE MAY BE AMENDED, MODIFIED OR WAIVED EXCEPT IN A WRITING SIGNED BY LESSOR
AND LESSEE.

INITIALS    /s/ D.H      (LESSEE)     INITIALS   /s/ R.D.S     (LESSOR)
        ----------------                      ----------------

LESSEE:                               LESSOR:

CRITICAL PATH, INC.                   LIGHTHOUSE CAPITAL PARTNERS II, L.P.

By:  /s/ David Hayden                 By: LIGHTHOUSE MANAGEMENT
   ---------------------------------
                                          PARTNERS II, L.P., its general partner
Name:   David Hayden
      ------------------------------  
                                      By: LIGHTHOUSE CAPITAL
Title:  Chief Executive Officer           PARTNERS, INC., its general partner
       -----------------------------
                                      By: /s/ Richard D. Stubblefield
                                         ---------------------------------------

                                      Name:   Richard D. Stubblefield
                                            ------------------------------------
                                      Title:   Managing Director
                                             -----------------------------------

                                       9
<PAGE>
 

   LEASE LINE SCHEDULE NO. 01, dated April 28, 1998 ("Lease Line Schedule"),
                                       to
MASTER EQUIPMENT LEASE AGREEMENT NO. 203, dated April 28, 1998 ("Master Lease"),
                                 by and between
LIGHTHOUSE CAPITAL PARTNERS II, L.P., a Delaware limited partnership ("Lessor")
         and CRITICAL PATH, INC., a California corporation ("Lessee").

(All capitalized terms not otherwise defined herein shall have the meanings
given to such terms in the Master Lease.)

IN CONSIDERATION of the mutual covenants contained herein, the parties agree as
follows:

  Lease Line.  The total Lessor's Cost of all units of Equipment under all
Equipment Schedules pursuant to this Lease Line Schedule shall not exceed
$2,000,000 (the "Commitment").  "Lessor's Cost" means, with respect to a unit of
Equipment, the total cost to Lessor of purchasing such unit, as indicated on the
applicable Equipment Schedule.  Lessor's obligation to fund Equipment Schedules
under the Commitment shall terminate on April 30, 1999 (the "Commitment
Termination Date").  The minimum Lessor's Cost for each Delivery & Acceptance
Certificate shall be $10,000.00.

  Rental Factor.  The Rental Factor for each Equipment Schedule will be 3.069%
of scheduled Lessor's Cost per month, payable monthly in advance.  The Rental
Payment under a particular Equipment Schedule shall be an amount equal to the
product of (a) the Rental Factor and (b) the aggregate Lessor's Cost of
Equipment subject to such Equipment Schedule.

  Interim Rent.   None.

  Eligible Equipment.  All equipment to be financed under an Equipment Schedule
must be Eligible Equipment.  "Eligible Equipment" means the following types of
equipment to the extent acceptable to Lessor:

  Various new and used computers, peripherals, analytical and test equipment,
laboratory equipment and furniture, office furniture and equipment, software in
an amount not to exceed $600,000, and other equipment as mutually agreed to by
Lessee and Lessor, together with all replacements, parts, cables, repairs,
additions and accessories incorporated therein or affixed thereto and all
operating manuals and manufacturer's instructions (collectively hereinafter
called the "Equipment").  Such replacements, parts, cables, repairs, additions
and accessories shall (whether or not purchased by Lessor) be considered part of
the Equipment for all purposes and, when installed in or attached to the
Equipment (unless otherwise agreed), be or become the property of the Lessor.
Except as otherwise specifically provided or the context so requires, the term
"Equipment" includes operating system or other bundled software which is
delivered on or with the Equipment or is included on the Equipment Schedules.

  Commencement Date.  The "Commencement Date" for each Equipment Schedule shall
be the first day of the calendar month  following the Acceptance Date for the
items of Equipment subject to such Equipment Schedule.

  Lease Termination Options.  Upon Lease Termination (as defined in the Master
Lease), Lessee will have, with respect to all but not less than all of the
Equipment governed by this Lease Line Schedule, the option to (a) purchase the
Equipment for the lesser of its then fair market value or fifteen percent (15%)
of Lessor's Cost, (b) renew the Lease or (c) return the Equipment to Lessor as
provided in Section 6 of the Master Lease.

  Advance Notice Period.  The "Advance Notice Period" shall be at least ninety
(90) days, but not more than 180 days, prior to Lease Termination (as defined in
the Master Lease) of Equipment Schedule No. 01 to this Lease Line Schedule.

  Automatic Extension Period.  The "Automatic Extension Period" shall equal
three (3) months and affects each Equipment Schedule under this Lease Line
Schedule.

                                       1
<PAGE>
 
  Insurance.  The amount of commercial general liability insurance (other than
products liability coverage and completed operations insurance) required under
the Master Lease shall be at least $2,000,000 per occurrence.  The amount of the
products liability and completed operations insurance under the Master Lease
shall be at least $2,000,000 per occurrence.

  Financial Statements.  Lessee shall deliver to Lessor:  (a) as soon as
available, but in any event within forty five (45) days after the end of each
month, a company prepared balance sheet, income statement and cash flow
statement covering Lessee's operations during such period, certified by an
officer of Lessee reasonably acceptable to Lessor; (b) as soon as available, but
in any event within one hundred twenty (120) days after the end of Lessee's
fiscal year, audited financial statements of Lessee prepared in accordance with
generally accepted accounting principles, consistently applied, together with an
unqualified opinion on such financial statements of an independent certified
public accounting firm reasonably acceptable to Lessor; (c) promptly upon
becoming available, copies of all statements, reports, budgets, sales
projections, operating plans and notices sent or made available generally by
Lessee to its security holders; (d) immediately upon receipt of notice thereof,
a report of any material legal actions pending or threatened against Lessee; and
(e) such other financial information as Lessor may reasonably request from time
to time.

  Maintenance Service Contracts.  Lessee shall obtain and keep in effect at all
times during the Lease Term (and any renewal or extension thereof), maintenance
service contracts covering the Equipment with the Equipment supplier or with
suppliers of maintenance services approved by Lessor, such approval not to be
unreasonably withheld.

  Installation, Handling and Delivery Charges.  Any handling and delivery charge
to cover all Equipment transportation, rigging, drayage, packing, installation
and handling to and from vendor's plant and upon return to Lessor's designated
location shall be paid by Lessee.

  Miscellaneous taxes. Without limitation of the provisions of the Master Lease,
Lessee agrees to pay and to indemnify Lessor for any sales or use tax and any
property tax in connection with the sale, lease or use of the Equipment.

  Late Fee.  Lessee shall pay a late charge on any rent payments or other sums
due hereunder which are past due, in an amount equal to 2% of the past due
amount, payable on demand.

Default Rate.  The Default Rate of interest on late payments shall be eighteen
percent (18%) per annum.

  Notices.  All notices shall be addressed as follows:

<TABLE>
<CAPTION>
 
     If to Lessor:                              If to Lessee:
     <S>                                        <C>
 
     Lighthouse Capital Partners II, L.P.      Critical Path, Inc.
     100 Drake's Landing, Suite 260            320 First Street
     Greenbrae, CA 94904-3121                  San Francisco, CA 94105
     Attn.:  Contract Administration           Attn.:  Chief Executive Officer
     Phone: (415) 925-3370                     Phone: (415) 543-2800
     Fax: (415) 925-3387                       Fax: (415) 543-2830
</TABLE>

     Conditions to the First Equipment Schedule.  On or prior to the date of
execution of the first Equipment Schedule under this Lease Line Schedule, Lessor
shall have received in form and substance satisfactory to Lessor, each of the
following:

     1. A Warrant substantially in the form of Exhibit H to the Master Lease.

     2. Copies, certified by the Secretary or Assistant Secretary or Chief
        Financial Officer of Lessee, of: (i) the Articles of Incorporation and
        By-Laws of Lessee (as amended to the date of the Lease) and

                                       2
<PAGE>
 
        (ii) the resolutions adopted by Lessee's board of directors authorizing
        the execution and delivery of this Lease, the Lease Line Schedule, the
        Equipment Schedules, the Warrant and the other documents referred in
        this Lease Line Schedule and the performance by Lessee of its
        obligations in such documents.

     3. A Good Standing Certificate (including franchise tax status) with
        respect to Lessee from Lessee's state of incorporation, dated a date
        reasonably close to the date of acceptance of the Lease by Lessor.

     4. A Software Rider substantially in the form of Annex B to this Lease Line
        Schedule.

     5. Evidence of the insurance coverage required by Section 8 of the Master
        Lease.

     6. All necessary consents of shareholders and other third parties with
        respect to the subject matter of the Master Lease, the Lease Line
        Schedule, the Equipment Schedules and the Warrant.

     Conditions to all fundings under all Equipment Schedules.  On or prior to
each funding under each Equipment Schedule under this Lease Line Schedule, each
of the following conditions shall have been satisfied:

     1. No Event of Default or event which, with notice or lapse of time or
        both, would become an Event of Default, has occurred and is continuing.

     2. Lessor shall have received a Software Licenses Assignment Agreement in
        substantially the form of Annex B-1 to this Lease Line Schedule with
        respect to each Vendor of software to be financed under this Lease Line
        Schedule.

     3. Lessor shall have received all necessary or desirable estoppel
        certificates and UCC filings, releases or terminations.

     4. Lessor shall have received a landlord waiver and consent in 
        substantially the form of Exhibit E to the Master Lease with respect to
        each equipment location.

     5. There shall not have occurred (i) any material adverse change to the
        general affairs, management, results of operations, condition (financial
        or otherwise) or prospects of Lessee, whether or not arising from
        transactions in the ordinary course of business, or (ii) any material
        adverse deviation by Lessee from the business plan of Lessee presented
        to and not disapproved by Lessor, since the date of the Master Lease.

     6. Lessee shall have delivered to Lessor an Equipment Schedule covering the
        appropriate funding period.

     7. Lessee shall have delivered to Lessor (i) in the case of a sale-
        leaseback, original vendor invoices, copies of canceled checks or other
        proof of payment, a Bill of Sale, a Delivery and Acceptance Certificate,
        and any UCC filings or other notices deemed necessary or desirable in
        connection with the sale-leaseback or (ii) at Lessor's request, in the
        case of a purchase of new equipment in excess of $50,000 from an
        equipment vendor, a Purchase Order and Invoice Assignment and a Delivery
        and Acceptance Certificate.

                                       3
<PAGE>
 
     8. All terms and conditions in the Equipment Schedule shall have been
        satisfied by the Acceptance Date for the Equipment under such Equipment
        Schedule.

     All other documents as Lessor shall have reasonably requested.

LESSEE:                             LESSOR:

CRITICAL PATH, INC.                 LIGHTHOUSE CAPITAL PARTNERS II, L.P.

By: /s/ David Hayden                By:  LIGHTHOUSE MANAGEMENT
   -----------------------------         PARTNERS II, L.P., its general partner
Name:   David Hayden
        ------------------------            
                                    By:  LIGHTHOUSE CAPITAL
Title:  Chief Executive Officer          PARTNERS, INC., its general partner
        ------------------------                      
                 
                                    By: /s/ Thomas Conneely
                                       -----------------------------------------

                                    Name:   Thomas Conneely
                                            ------------------------------------
                                    Title:  Vice President, Operations
                                            ------------------------------------

Annex A      -      Stipulated Loss Value Table

                                       4
<PAGE>
 
                                    Annex A
                                        
                          STIPULATED LOSS VALUE TABLE
                                       TO
              LEASE LINE SCHEDULE NO. 01, dated April 28, 1998, to
MASTER EQUIPMENT LEASE AGREEMENT NO. 203, dated April 28, 1998 ("Master Lease"),
    by and between LIGHTHOUSE CAPITAL PARTNERS II, L.P., a Delaware limited
   partnership ("Lessor"), and CRITICAL PATH, INC., a California corporation
                                  ("Lessee").

(All capitalized terms not otherwise defined herein shall have the meanings
given to such terms in the Master Lease.)

In the case of an Event of Loss, the Stipulated Loss Value for each item of
leased Equipment is the Lessor's Cost for the item multiplied by Stipulated Loss
Value Percentage for the Rent Payment Number following the month of the Event of
Loss.

<TABLE>
<CAPTION>


             Stipulated                               Stipulated
Rent         Loss               Rent                  Loss
Payment      Value              Payment               Value
Number       Percentage         Number                Percentage
-------      ----------         -------               -----------
<S>          <C>                <C>                   <C>
   1         111.88%            19                    65.61%
   2         109.78%            20                    62.81%
   3         106.95%            21                    59.98%
   4         104.54%            22                    57.13%
   5         102.11%            23                    54.25%
   6          99.65%            24                    51.34%
   7          97.18%            25                    48.41%
   8          94.68%            26                    45.45%
   9          92.16%            27                    42.67%
   10        89.627%            28                    39.46%
   11         87.01%            29                    36.44%
   12         84.46%            30                    33.39%
   13         81.84%            31                    30.31%
   14         79.20%            32                    27.21%
   15         76.53%            33                    24.08%
   16         73.84%            34                    20.93%
   17         71.12%            35                    17.75%
   18         68.38%            36 and thereafter     15.00%
</TABLE>
 
Lessee:  ____________________      Lessor:  ____________________

                                       5
