<PAGE>

                                                                   EXHIBIT 10.30

                               Table of Contents
                               -----------------


<TABLE>
<S>                                                            <C>
Defined Terms................................................   1
The Premises.................................................   3
Term.........................................................   4
Basic Annual Rent............................................   4
Additional Annual Rent.......................................   4
Tenant's Proportionate Share of Building Operating Expenses..   5
Rent Increase................................................   8
Construction of Tenant Improvements..........................   8
Use of Demised Premises......................................   8
Upkeep of Demised Premises...................................   8
Subletting and Assignment....................................   8
Fire Insurance...............................................  10
Alterations..................................................  10
Signs; Furnishings...........................................  11
Tenant's Equipment...........................................  12
Access.......................................................  12
Rules and Regulations........................................  13
Damage to Demised Premises...................................  13
Tenant's Property............................................  14
Liability....................................................  14
Insurance....................................................  15
Services.....................................................  15
Defaults and Remedies........................................  16
Insolvency...................................................  16
Condemnation.................................................  17
Security Deposit.............................................  17
Holding Over.................................................  17
Possession...................................................  18
Ground or Underlying Lease...................................  18
Subordination................................................  18
Approval.....................................................  19
Right to Cure Defaults.......................................  19
Construction Plans...........................................  19
Parking......................................................  19
Indemnity of Landlord........................................  20
Successors...................................................  20
No Partnership...............................................  20
No Representation by Landlord................................  20
Waiver of Jury Trial.........................................  20
Pronouns.....................................................  20
Invalidity of Provisions.....................................  20
Governing Law................................................  21
Headings.....................................................  21
Entire Agreement.............................................  21
No Offer or Option...........................................  21
Notices......................................................  21
Special Terms and Conditions.................................  21
Time of Essence and Consents.................................  21
</TABLE>
<PAGE>

                                 NRTC BUILDING
                                 OFFICE LEASE

     THIS LEASE is made as of this 1st day of February, 2000 by and between
NATIONAL RURAL UTILITIES COOPERATIVE FINANCE CORPORATION (hereinafter called the
"Landlord") and INVENTA CORPORATION, a corporation formed under the laws of the
State of California (hereinafter called the "Tenant").

     In consideration of the mutual agreements hereinafter set forth, the
parties hereto agree as follows:

     1.   Defined Terms.
          --------------

          A.  "Additional Annual Rent" shall mean the addition to the Basic
     Annual Rent for each year of the term of this Lease on the first day of
     each Fiscal Year in the amount of the increase of Tenant's Proportionate
     Share of Building Operating Expenses for a particular Fiscal Year, or
     portion thereof.

          B.  "Base Fiscal Year" shall mean the period from June 1, 2000 through
     May 31, 2001.

          C.  "Basic Annual Rent" shall mean the rent for the Demised Premises
     in the sum of Two Hundred Sixty Three Thousand Six Hundred Ten and 00/100
     Dollars ($263,610.00) annually, being Twenty One Thousand Nine Hundred
     Sixty Seven and 50/100 Dollars ($21,967.50) monthly.

          D.  "Building" shall mean the structure known as the NRTC Building
     located at and known by the street address of Woodland Park, 2121
     Cooperative Way, Herndon, Virginia 20171-3025, and, to the extent of the
     Landlord's interest, the driveways, walkways and parking areas.

          E.  "Building Expense Percentage" shall mean the percentage determined
     by dividing the Demised Premises area, as specified in Paragraph 1.G. of
     the Lease provisions, by the total rentable area in the Building, said
     percentage being 5.4%.

          F.  "Common Areas" shall mean the Building common, corridors,
     stairways, and elevators, the common walkways, loading dock and driveways
     necessary for access to the Building, the common toilets, corridors and
     elevator lobbies of any multi-tenant floor, and the parking areas for the
     Building, but excluding the meeting rooms and other meeting facilities
     located on the first level of the Building.

          G.  "Demised Premises" shall mean the 9,090 square feet of space (as
     determined by the modified Washington Board of Realtors method) on the
     first floor of the Building and as shown on Exhibit A attached hereto.

          H.  "Fiscal Year" shall mean the twelve month period from June 1
     through May 31.

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<PAGE>

          I.  "Landlord" shall mean National Rural Utilities Cooperative Finance
     Corporation, its successor and assigns.

          J.  "Lease Commencement Date" shall mean the business day after the
     date that Landlord or the Contractor (as defined in Paragraph 6 below)
     notifies Tenant in writing that all Tenant Improvements (as defined in
     Paragraph 6 below) have been substantially completed in accordance with the
     approved Construction Plans (as defined in Paragraph 6 below) (exclusive of
     Punch List Items (as defined below) and Tenant approved "long lead" items)
     and the Demised Premises are in in broom clean condition. As used herein,
     the term "Substantial Completion" (or its grammatical variations) with
     respect to the Demised Premises shall mean when the Tenant Improvements (or
     so much of the Tenant Improvements which are not dependent upon prior
     installation or completion of long-lead items) to be performed by Landlord
     in the Demised Premises in accordance with the approved Construction Plans,
     and any approved revisions to such approved Construction Plans shall have
     been completed, and reasonable means of access and facilities necessary to
     Tenant's beneficial use and occupancy of the Demised Premises, including
     corridors, toilets, elevators, stairways and HVAC, sanitary water, parking
     and electrical facilities have been installed and are available to Tenant,
     notwithstanding (i) the fact that minor or insubstantial details of
     construction, mechanical adjustment or decoration remain to be performed,
     the non-completion of which does not materially adversely interfere with
     Tenant's beneficial use of the Demised Premises, and (ii) any incomplete
     items of construction, mechanical adjustment or decoration which are
     incomplete as a result of Tenant's failure in providing, supplying, or
     constructing any portion of the Tenant Improvements where Tenant is
     responsible for such completion. Said facilities shall not be deemed to be
     unavailable and shall not affect substantial completion if only minor or
     insubstantial details or construction, decoration or mechanical adjustment
     ("Punch List Items") remain to be done.

          K.  "Lease Expiration Date" shall mean the date that is the day before
     five (5) years from the Lease Commencement Date.

          L.  "Security Deposit" shall mean the sum of One Hundred Ninety Seven
     Thousand Seven Hundred Seven and 50/100 Dollars ($197,707.50) that the
     Tenant agrees to deposit with the Landlord upon execution and delivery of
     this Lease and to be held by the Landlord as set forth in Paragraph 24
     hereof. In lieu of the cash Security Deposit referred to above, Tenant may
     deliver to Landlord, and shall maintain in effect at all times during the
     Term of this Lease following delivery hereof, a clean, unconditional and
     irrevocable letter of credit, substantially in the form of Exhibit B
     attached hereto (the "Letter of Credit") in the stated amount of One
     Hundred Ninety Seven Thousand Seven Hundred Seven and 50/100 Dollars
     ($197,707.50) (the "L/C Amount").

          Any such Letter of Credit shall: (i) be issued by a commercial bank
     reasonably satisfactory to Landlord ("Issuer"); (ii) be a standby, at-
     sight, irrevocable letter of credit; (iii) be payable to Landlord; (iv)
     require that any draw on the Letter of Credit be made only upon receipt by
     the Issuer of the original Letter of Credit and a sight draft or multiple
     partial sight drafts, without presentation of any other documents,
     statements or authorizations; (v) not expire prior to one year or longer
     after the date of its issuance and shall provide that it shall be
     automatically renewed from year to year unless

                                       2
<PAGE>

     terminated by the Issuer by notice to the Landlord given not less than
     sixty (60) days prior to the then expiration date thereof by certified or
     registered mail; (vi) provide that it is governed by the International
     Standby Practices 1998 published by the International Chamber of Commerce,
     Publication No. 590; and (vii) provide for a final expiration date
     (including any renewals) no earlier than ninety (90) days after the Lease
     Expiration Date.

          Landlord may draw upon such Letter of Credit, in whole or in part (at
     Landlord's option), if: (i) Tenant defaults with respect to any of the
     terms, conditions and covenants of this Lease on the Tenant's part to be
     observed or performed, including, but not limited to, the payment of rent
     or additional rent, and such default continues beyond the applicable grace
     period, if any, or (ii) Tenant, or anyone holding possession of the Demised
     Premises through Tenant, holds over in the Demised Premises after the
     expiration or sooner termination of the Term of this Lease; or (iii)
     Landlord is given notice that Issuer is terminating such Letter of Credit,
     or (iv) such Letter of Credit expires as of a stated date by its terms and
     is not replaced with a letter of credit meeting the criteria set forth in
     this Paragraph 1.L. at least thirty (30) days prior to such Letter of
     Credit's stated expiration date.

          Landlord may use, apply or retain the proceeds of the Letter of Credit
     to the same extent Landlord may use, apply or retain the Security Deposit,
     as set forth in Paragraph 24 hereof. Landlord shall only draw upon the
     Letter of Credit to the extent required to cure Tenant's default hereunder.
     !f Landlord partially draws down the Letter of Credit, Tenant shall, within
     fifteen (15) days after Landlord gives Tenant notice thereof, cause the
     amount of the Letter of Credit to be increased to the L/C Amount, or
     substitute cash security instead. If Tenant fully and faithfully complies
     with all of the terms, conditions and covenants of this Lease, any Letter
     of Credit, or any remaining portion of any sum collected by Landlord
     hereunder through a draw on such Letter of Credit, shall be returned to
     Tenant within sixty (60) days after the Lease Expiration Date and delivery
     of possession of the Demised Premises to Landlord in accordance with the
     provisions of this Lease.

          In the event Landlord transfers its interest in this Lease, Landlord
     may transfer the Security Deposit, including the Letter of Credit, to the
     transferee of the Landlord (the "Transferee"). If the Security Deposit is
     so transferred, Landlord shall thereupon be released from liability for the
     return of the Security Deposit, including the Letter of Credit, and Tenant
     shall look solely to the Transferee for the return of the Security Deposit
     in accordance with the terms of this Lease. The provisions of this
     paragraph shall apply to every such transfer of this Lease. If Landlord
     desires to transfer the Letter of Credit to such Transferee, Tenant shall
     cooperate in effecting such transfer; and Tenant shall pay the Issuer's
     usual and customary fee for transferring such Letter of Credit.

          If, on the dates hereinafter mentioned and referred to (i) no event
     which would constitute an event of default under Paragraph 21 hereof shall
     have occurred, regardless of whether such default has been cured, (ii) no
     event described in Paragraph 22 hereof shall have occurred, regardless of
     whether such event has been cured or whether any applicable cure period has
     lapsed, and (iii) Tenant shall have satisfied all of its other obligations
     under this Lease, Landlord agrees that the amount of the Security Deposit
     required hereunder (whether by Letter of Credit or cash) shall be reduced
     to

                                       3
<PAGE>

     One Hundred Thirty One Thousand Eight Hundred Two and 00/100 Dollars
     ($131,802.00) at the beginning of the 13th month of the term hereof, to
     Sixty Five Thousand Nine Hundred Two and 50/100 ($65,902.50) at the
     beginning of the 25th month of the term hereof, and to Twenty One Thousand
     Nine Hundred Sixty Seven and 50/100 Dollars ($21,967.50) at the beginning
     of the 37th month of the term hereof.

          Tenant shall have the right to substitute one letter of credit for
     another if the substitute letter of credit meets the requirements of this
     Paragraph 1.L. In addition, Tenant shall substitute another letter of
     credit meeting the requirements of this Paragraph 1.L. if the Issuer which
     has issued the Letter of Credit becomes insolvent or if the Letter of
     Credit is void, unenforceable or uncollectible. If the Issuer which has
     issued the Letter of Credit becomes unacceptable to Landlord for good
     reason, Tenant shall, within fifteen (15) days after notice is given Tenant
     by Landlord, deliver to Landlord either a substitute letter of credit
     meeting the requirements of this Paragraph 1.L. or cash security in the L/C
     Amount.

          If Landlord at any time, or from time to time, requests any reasonable
     change in the terms, conditions or provisions of such Letter of Credit,
     Tenant shall promptly cause such Letter of Credit to be so modified. If the
     Letter of Credit is lost, mutilated, stolen or destroyed, Tenant shall
     cooperate with Landlord's efforts to cause the Issuer to cancel the lost,
     mutilated, stolen or destroyed Letter of Credit and to replace such Letter
     of Credit.

     2.   The Premises. The Landlord hereby leases to the Tenant and the Tenant
          ------------
hereby leases from the Landlord, for the Term and upon the conditions
hereinafter provided, the Demised Premises.

     3.  Term. The term of this Lease ("Term") shall be for a period of five (5)
         ----
years (or until such term shall sooner cease and expire as hereinafter provided)
commencing on the Lease Commencement Date and expiring on the Lease Expiration
Date, both dates inclusive.

     4.  Basic Annual Rent. The Tenant shall pay as rent for the Demised
         -----------------
Premises the sum of Two Hundred Sixty Three Thousand Six Hundred Ten and 00/100
Dollars ($263,610.00) annually, which results in a term rent of One Million
Three Hundred Eighteen Thousand Fifty and 00/100 ($1,318,050.00), payable in
equal monthly installments, in advance, of Twenty One Thousand Nine Hundred
Sixty Seven and 50/100 Dollars ($21,967.50), the first monthly installment to be
paid upon the execution and delivery of this Lease, the second and subsequent
monthly installments to be made on the first day of each and every calendar
month during the term hereof. The Tenant will pay all rent due under this Lease
to the Landlord, at its office or to such other party or to such other address
as the Landlord may designate from time to time by written notice to the Tenant,
without demand and without deduction, set-off or counterclaim. If the Landlord
shall at any time or times accept said rent after it shall become due and
payable, such acceptance shall not excuse delay upon subsequent occasions, or
constitute, or be construed as, a waiver of any of the Landlord's rights
hereunder or any other rights available to the Landlord as provided for by law.

     5.  Additional Annual Rent. In addition to the Basic Annual Rent specified
         ----------------------
above, Tenant shall pay to Landlord as Additional Annual Rent for the Premises,
in each Fiscal Year or partial Fiscal Year during the Term of this Lease,
commencing with the next Fiscal Year, an amount equal to any increase in the
Tenant's Proportionate Share of Building Operating

                                       4
<PAGE>

Expenses for such Fiscal Year which exceeds the Tenant's Proportionate Share of
Building Operating Expenses for the Base Fiscal Year.

     A.  The Tenant's "Proportionate Share of Building Operating Expenses" shall
mean the dollar amount equal to the product of Tenant's Building Expense
Percentage as stated in Paragraph 1.E. of the Lease times the Building Operating
Expenses.

     The term "Building Operating Expenses" shall mean all of Landlord's direct
costs and expenses paid or incurred in operating and maintaining the Building
for a particular Fiscal Year or portion thereof as determined by Landlord in
accordance with generally accepted accounting principles, including all
additional direct costs and expenses of operation and maintenance of the
Building which Landlord determines that it would have paid or incurred during
such year if the Building had been ninety five percent (95%) occupied. Building
Operating Expenses shall include by way of illustration but not limitation: all
general Real Estate Taxes (as defined below) and all special assessments;
insurance premiums; water, sewer, electrical and other utility charges;
assessments, including special assessments imposed by Woodland Park Association
or successors; service and other charges incurred in the operation and
maintenance of the elevators and the heating, ventilation and air-conditioning
system; cleaning and other janitorial services; tools and supplies; repair
costs; exterior and interior landscape maintenance costs; security services;
license, permit and inspection fees; costs and expenses (including reasonable
fees of counsel) to the extent such expenses are reasonable and customary, in
connection with contesting the validity or amount of any tax, governmental or
utility charge or assessment; wages and related benefits payable to employees
principally engaged in the management, maintenance and operation of the
Building; and, in general, all other costs and expenses, including those which
would normally be amortized over a period not to exceed five (5) years. The term
"Real Estate Taxes" shall mean any taxes, assessments, levies, impositions or
charges now levied, assessed or imposed on real estate and the improvements
thereon. "Real Estate Taxes" shall not include any inheritance, estate,
succession, transfer, gift tax nor capital levy and further, no franchise,
corporation, income or profit tax calculated upon the Landlord's net income
shall be passed through to the Tenant, except to the extent that if at any time
during the Term of this Lease the methods of taxation prevailing at the
commencement of the Term of this Lease shall be altered so that in lieu of, as a
substitution for or in addition to the whole or any part of the Real Estate
Taxes there shall be levied, assessed or imposed a tax, assessment, levy, fee or
other charge: (1) on or measured by the rents received therefrom; (2) measured
by or based in whole or in part upon the Building and imposed upon Landlord; or
(3) measured by the rent payable by Tenant under this Lease, then all such
taxes, assessments, levies, impositions, charges or fees to the part thereof so
measured or based, shall be deemed to be included within the term "Real Estate
Taxes". Landlord hereby agrees to provide Tenant, to the extent possible,
courtesy notice of special assessments, except real estate property tax
assessments; provided, however, that failure by Landlord to give such courtesy
notice shall not be a breach of Landlord's obligations hereunder and shall not
alter or amend any of Tenant's obligations hereunder. There shall also be
included in Building Operating Expenses the cost of any capital improvement made
to the Building by Landlord after the date of this Lease which is required under
any governmental law or regulation that was not applicable to the Building at
the time it was constructed, amortized over such period as Landlord shall
reasonably determine, together with interest at the Prevailing Bank Prime Rate
plus two percent (2%) per annum on the unamortized balance. The "Prevailing Bank
Prime Rate" shall mean the bank prime rate published in the "Money Rates" column
of The Wall Street Journal in its last publication of that column in the
preceding month; provided, however, if The Wall Street Journal shall cease to be
published, then the Bank Prime

                                       5
<PAGE>

Rate shall be determined by Landlord by reference to another recognized
publication reporting bank prime rates.

     Notwithstanding anything to the contrary set forth above, the term
"Building Operating Expenses" shall not include:

     (i)    Costs of work, including painting and decorating, which Landlord
performs for any tenant (including Tenant) other than work of a kind and scope
which Landlord is obligated to furnish to all tenants whose leases contain a
rental adjustment provision similar to this one;

     (ii)   Costs of repairs or other work occasioned by fire, earthquake,
windstorm or other casualty, except for a reasonable deductible under any
insurance policy; and costs of remediating hazardous materials (except to the
extent that any such costs arise in the course of ordinary maintenance or result
from Tenant's acts or omissions);

     (iii)  Leasing commissions, advertising expenses, and other costs incurred
in leasing space in the Building;

     (iv)   Costs of repairs or rebuilding necessitated by condemnation;

     (v)    Interest on borrowed money or debt amortization, except as
specifically set forth above;

     (vi)   Costs for which Landlord has a right to reimbursement (other than
under the Building Operating Expense pass-through provisions of all leases in
the Building) or has been reimbursed or receives a credit, refund or discount
that is covered under a warranties, including a warranty applicable to the
initial construction of the Building;

     (vii)  Costs of a capital nature as determined all in accordance with
generally accepted accounting principles consistently applied, except as
expressly permitted to be included in Building Operating Expenses;

     (viii) Costs incurred by Landlord due to any violation of the terms and
conditions of any lease of space or occupancy agreement in the Building, or in
resolving any dispute with a tenant or occupant of the Building;

     (ix)   Costs of, and the overhead and profit increment paid to Landlord,
or to affiliates or partners of Landlord, or to partners or affiliates of such
partners, for goods and/or services supplied to or used in the Building to the
extent the same exceed the costs or the overhead and profit increment, as the
case may be, of such goods and/or services rendered by unaffiliated third
parties on a competitive basis; or

     (x)    Depreciation on the Building.

     If Landlord shall install a labor-saving device or other equipment which
improves the operating efficiency of any system within the Building (such as
energy efficient lighting controls) and thereby reduces Building Operating
Expenses, then Landlord may add to Building Operating Expenses in each year
during the useful life of such installed device or equipment an amount equal to
the annual amortization allowance of the cost of such installed device or
equipment as determined in accordance with applicable regulations of the
Internal Revenue

                                       6
<PAGE>

Service or generally accepted accounting principles, together with interest at
the Prevailing Bank Prime Rate plus two percent (2%) per annum on the
unamortized balance thereof, provided, however, that the amount of such
allowance and interest shall not exceed the annual cost or expense reduction
attributed by Landlord to such installed device or equipment; and further
provided, that in no event shall such allowance and interest increase Tenant's
Additional Annual Rent over what it would have been if such labor-saving device
or other equipment had not been installed.

     (1) Payment of Tenant's Proportionate Share of Building Operating Expenses.
         ----------------------------------------------------------------------
Tenant's Proportionate Share of Building Operating Expenses for each Fiscal Year
shall be estimated annually by Landlord, and written notice thereof shall be
given to Tenant at least thirty (30) days prior to the beginning of each Fiscal
Year. Tenant shall pay to Landlord each month as rent commencing with the first
month of the Fiscal Year, at the same time the Basic Rent is due, an amount
equal to one-twelfth (1/12) of any increase in the estimated Tenant's
Proportionate Share of Building Operating Expenses.

     (2) Revisions in Estimated Tenant's Proportionate Share of Building
         ---------------------------------------------------------------
Operating Expenses. If real estate taxes or the cost of utility, janitorial
-------------------
services, or other building operations increase during a Fiscal Year, Landlord
may revise the estimated Tenant's Proportionate Share of Building Operating
Expenses one time during such year by giving Tenant written notice to that
effect, and thereafter Tenant shall pay to Landlord, in each of the remaining
months of such year, an amount equal to the amount of such increase in the
estimated Additional Annual Rent divided by the number of months remaining in
such year.

     (3) Adjustments to Actual Tenant's Proportionate Share of Building
         --------------------------------------------------------------
Operating Expenses. Within ninety (90) days after the end of each Fiscal Year,
------------------
Landlord shall prepare and deliver to Tenant a reasonably itemized statement
showing the actual Tenant's Proportionate Share of Building Operating Expenses.
Within thirty (30) days after receipt of the aforementioned statement, Tenant
shall pay to Landlord, or Landlord shall credit against the next Rent payment or
payments due from Tenant, as the case may be, the difference between the actual
Tenant's Proportionate Share of Building Operating Expenses for the preceding
Fiscal Year and the estimated Tenant's Proportionate Share of Building Operating
Expenses paid by Tenant during such year. The amount of any such difference
shall be determined by the Landlord's audit of its books.

     If Tenant disputes an statement submitted by Landlord or a proposed
increase or decrease in the actual Tenant's Proportionate Share of Building
Operating Expenses, Tenant shall give Landlord written notice of such dispute
within ninety (90) days after Tenant's receipt of the statement. If Tenant does
not give Landlord timely notice, Tenant waives its right to dispute the
particular statement. If Tenant timely objects, Tenant may engage its own
certified public accountants ("Tenant's Accountants") to verify the accuracy of
the statement complained of or the reasonableness of the estimated increase or
decrease. If Tenant's Accountants determine that an error has been made,
Landlord's accountants and Tenant's Accountants shall endeavor to agree upon the
matter, failing which such matter shall be submitted to an independent certified
public accountant selected by Landlord, with Tenant's approval, which shall not
be unreasonably withheld, delayed or conditioned, at Tenant's sole cost and
expense, for a determination which will be conclusive and binding upon Landlord
and Tenant. Notwithstanding the pendency of any dispute, Tenant shall continue
to pay Landlord the amount of the aforementioned statement determined by
Landlord's accountants until the statement has been determined to be incorrect.
If

                                       7
<PAGE>

it is determined that any portion of the Building Operating Expenses were not
properly chargeable to Tenant, then Landlord shall promptly credit or refund the
appropriate sum to Tenant.

     B.  Rent Increase. In addition to all rents hereinabove set forth in this
         -------------
Lease it is further understood and agreed that each monthly payment of the Basic
Annual Rent shall be increased for each year of the term of this Lease on the
anniversary day of the Lease Commencement Date by an amount equal to one-twelfth
(1/12) of three percent (3%) of the previous year's Basic Annual Rent.

     6.  Construction of Tenant Improvements. Landlord agrees, prior to the
         -----------------------------------
Lease Commencement Date, to construct improvements to the Demised Premises
substantially in accordance with the Construction Plans (as defined below) using
standard building materials and based upon a mutually agreeable space plan, at
Landlord's sole cost and expense (the "Tenant Improvements"). Subject to the
provisions herein, Landlord shall submit to Tenant design drawings and working
drawings prepared by Landlord's architect and engineers (including mechanical,
electrical and plumbing drawings) for all of the Tenant Improvements including,
but not limited to, the partition, electric and telephone outlets and all other
requirements of Tenant (collectively, the "Construction Plans"), which shall be
subject to the approval of Tenant, which approval shall not be unreasonably
withheld. Upon approval by Tenant of the Construction Plans, Landlord shall
select a general contractor (the "Contractor") for the purpose of constructing
the Tenant Improvements from bids submitted by general contractors whose
qualifications have been approved by Landlord.

     7.  Use of Demised Premises. The Tenant will use and occupy the Demised
         -----------------------
Premises solely for general office purposes (and for uses ancillary thereto) and
in accordance with the use permitted under applicable zoning regulations and the
Declaration of Protective Covenants for Woodland Park, recorded in the Clerk's
Office for the Circuit Court for Fairfax County, Virginia, in Deed Book 6324, at
Page 514, and any amendments thereto (as amended, the "Covenants"). Without the
prior written consent of the Landlord, the Demised Premises will not be used for
any other purpose. The Tenant will not use or occupy the Demised Premises for
any unlawful purpose, and will comply with all present and future laws,
ordinances, regulations, and orders of the United States of America, the
Commonwealth of Virginia and any other public or non-public authority having
jurisdiction over the Demised Premises; provided, however, that Tenant shall not
be obligated to make any changes, additions or improvements to the structural
elements of the Building.

     8.  Upkeep of Demised Premises. The Tenant agrees to keep the Demised
         --------------------------
Premises and the fixtures therein in good order and condition and will, on the
Lease Expiration Date or other termination of the term of this Lease, surrender
the same, broom clean, in the same order and condition in which they were on the
Lease Commencement Date, ordinary wear and tear, Landlord's obligations and
damage by the elements excepted. The Tenant will not do or permit to be done any
act that will conflict with the regulations of the fire department or the fire
laws, or with any rules or ordinances established by the Board of Health or
other federal or local governmental authority.

     9.  Subletting and Assignment. The Tenant will not sublet or rent the
         -------------------------
Demised Premises or any part thereof or permit the use or occupancy thereof to
any person, firm or corporation, or transfer, assign, mortgage or encumber this
Lease, without the prior written consent of the Landlord; nor shall any
subletting or assignment or transfer of this Lease be effective without the
prior written consent of the Landlord. In the event that Tenant requests

                                       8
<PAGE>

Landlord's consent to sublet any part of the Demised Premises (which request
must be made in writing) such consent shall not be unreasonably withheld,
delayed or conditioned. Any such sublease shall contain provisions generally
consistent with the terms of this Lease and said sublease shall be provided to
Landlord for Landlord's approval, which shall not be unreasonably withheld,
delayed or conditioned. Tenant shall provide to Landlord a fully executed copy
of the sublease as soon as reasonably possible.

     Tenant agrees to pay Landlord, as additional rent, one-half (1/2) of any
profits which Tenant may secure in any such subleasing or assignment of any
space within the Demised Premises. Profits are any consideration received by the
Tenant for the subleased or assigned space in excess of what the Tenant is
paying as rent pursuant to this Lease for said space minus the recovery of any
prorated capital expenditures which were expended on the space and any expenses
which the Tenant may incur in securing the sublease or assignment. The
additional rent discussed in this section will be paid monthly to Landlord
during the period of the sublease or assignment. The Landlord shall have the
right to inspect the Tenant's books and records as well as any sublease or
assignment to determine the amount of profit obtained by reason of the
subletting or assignment.

     Any assignment, transfer or subletting without Landlord's written consent
shall be void, and shall, at the option of Landlord, constitute a default under
the terms of this Lease. Consent by the Landlord to any assignment or subletting
shall not be construed as a waiver or release of the Tenant from the terms of
any covenant or obligation under this Lease, nor shall the collection or
acceptance of rent from any such assignee, subtenant or occupant constitute a
waiver or release of the Tenant from the terms of any covenant or obligation
under this Lease, nor shall such assignment or subletting be construed to
relieve the Tenant from obtaining the consent in writing of the Landlord to any
further assignment or subletting. In the event that the Tenant defaults
hereunder, the Tenant hereby assigns to the Landlord the rent due from any
subtenant of the Tenant and hereby authorizes each such subtenant to pay said
rent directly to the Landlord.

     Notwithstanding the foregoing, Tenant may, without obtaining Landlord's
prior written consent, assign or sublease all or any portion of the Demised
Premises to the following parties on the following conditions: (i) any
subsidiary or affiliate in which Tenant has an ownership interest of more than
50%; (ii) any parent of Tenant; (iii) any subsidiary or affiliate in which
Tenant's parent owns by means of an ownership interest of more than 50%; or (iv)
any corporation into which Tenant may be merged or consolidated or which
purchases all or substantially all of the assets or stock of Tenant; so long as
such subtenant or assignee shall use and occupy the Demised Premises solely for
general office purposes (and for uses ancillary thereto) and in accordance with
the use permitted under applicable zoning regulations, the Covenants and the
other requirements set forth in Paragraph 7 hereof. Not less than thirty (30)
days prior to the effective date of such transaction, Tenant will provide
Landlord with documentation evidencing such transaction and such other evidence
as Landlord may reasonably require to establish that such transaction falls
within the terms and provisions of this paragraph. Furthermore, Tenant may allow
employees of companies to whom Tenant is providing products or services under
express short term contractual agreements, or with which Tenant is collaborating
in the development or provision of products or services under express short term
contractual agreements, to work in the Demised Premises without Landlord's
consent and without being deemed to have sublet any portion of the Demised
Premises, so long as such employees do not occupy space which is separated from
that occupied by Tenant by demising walls and the number of such employees does
not exceed twenty percent (20%) of the total number of persons regularly
occupying the

                                       9
<PAGE>

Demised Premises, the employees of such companies shall use and occupy the
Demised Premises solely for general office purposes (and for uses ancillary
thereto) and in accordance with the use permitted under applicable zoning
regulations, the Covenants and the other requirements set forth in Paragraph 7
hereof.

     10.  Fire Insurance. The Tenant will not conduct or permit to be conducted,
          --------------
any activity or place any equipment or substance in or about the Demised
Premises or the Building of which they form a part, which will in any way
increase the rate of fire or other insurance on said Building or on the property
kept therein. If any increase in the rate of fire or other insurance is stated
by any insurance company or by the applicable insurance rating bureau to be due
to such activity or equipment or substance in or about the Demised Premises,
such statement will be conclusive evidence that the increase in such rate is due
to such activity or equipment or substance in and about the Demised Premises
and, as a result thereof, the Tenant shall, at the option of the Landlord,
either reimburse the Landlord for such increase within thirty (30) days of the
mailing of notice to the Tenant of such increase in the insurance rate, or
promptly end such activity and/or remove such equipment or substance. The Tenant
shall continue to reimburse the Landlord for the entire period that its actions
or past actions caused an increase in the rate of insurance.

     11.  Alterations. The Tenant will not make or permit anyone to make any
          -----------
alterations, decorations, additions or improvements, structural or otherwise, in
or to the Demised Premises or the Building without the prior written consent of
the Landlord, which shall not be unreasonably withheld, delayed or conditioned.
All such alterations, decorations, additions or improvements, permitted by the
Landlord must conform to all statutes, rules and regulations, including fire
regulations, of the federal and local governments and any other public authority
having jurisdiction over the Demised Premises and the Building and will be at
the sole expense of the Tenant. As a condition subsequent to such written
consent of the Landlord, the Tenant agrees to obtain and deliver to the Landlord
written and unconditional waivers of mechanics' liens upon the Demised Premises
or the Building for all work, labor and or services to be performed, and
materials to be furnished, by them in connection with such work, signed by all
contractors, subcontractors, material men and laborers to become involved in
such work. If, notwithstanding the foregoing, any mechanic's lien is filed
against the Demised Premises or the Building for work claimed to have been done
for, or materials claimed to have been furnished to, the Tenant, such mechanic's
lien shall be discharged by the Tenant within ten (10) business days thereafter
at the Tenant's sole cost and expense by the payment thereof or by filing any
bond required by law. If the Tenant shall fail to discharge any such mechanic's
lien, the Landlord may, at its option, discharge the same and treat the cost
thereof as additional rent payable with the monthly installment of rent next
becoming due. It is hereby expressly covenanted and agreed that such discharge
by the Landlord shall not be deemed to waive or release the default of the
Tenant. It is understood and agreed by the Landlord and the Tenant that any such
alterations, decorations, additions or improvements shall be conducted on behalf
of the Tenant and not on behalf of the Landlord. It is further understood and
agreed that in the event the Landlord shall give its written consent to the
Tenant's making any such alterations, decorations, additions or improvements,
such written consent shall not be deemed to be an agreement or consent by the
Landlord to subject the Landlord's interest in the Demised Premises or the
Building to any mechanic's liens which may be filed in respect of any such
alterations, decorations, additions or improvements made by or on behalf of the
Tenant. The Tenant will indemnify and hold the Landlord harmless from and
against any and all expenses (including reasonable attorneys' fees), liens,
claims or damages to person or property which may or might arise by reason of
the making of any such alterations, decorations, additions or

                                      10
<PAGE>

improvements. If any such alterations, decorations, additions or improvements
are made without the prior written consent of the Landlord, the Landlord may
correct or remove the same, and the Tenant shall be liable for any and all
expenses incurred by the Landlord in the performance of this work. All
alterations, decorations, additions or improvements in or to the Demised
Premises or the Building made by either party (but not including moveable office
furniture and equipment not permanently affixed to the Demised Premises), shall,
at the election of the Landlord become the property of the Landlord and shall
remain upon the Demised Premises or the Building and be surrendered with the
Demised Premises at the end of the term hereof without disturbance, molestation
or injury. Should the Landlord elect that any alterations, decorations,
additions, improvements, installations, changes, or replacements made by the
Tenant upon the Demised Premises or the Building be removed upon termination of
this Lease, the Tenant hereby agrees to cause the same to be removed at the
Tenant's sole cost and should the Tenant fail to remove the same, then and in
such event, the Landlord may cause the same to be removed at the Tenant's
expense and the Tenant hereby agrees to reimburse the Landlord for the cost of
such removal together with any and all damages which the Landlord may suffer and
sustain by reason of the failure of the Tenant to remove the same. If expressly
requested by Tenant in connection with the Tenant's request for Landlord's
consent to any alterations proposed by the Tenant, Landlord shall inform the
Tenant whether Landlord will require the removal of such alterations pursuant to
this paragraph.

     12.  Signs; Furnishings. The Tenant agrees that no sign, advertisement or
          ------------------
notice shall be inscribed, painted, affixed or displayed on any part of the
outside or the inside (as long as not visible to the outside) of the Demised
Premises or the Building, except on the directories, locations specified by
Landlord and the doors of offices, and then only in such place, number, size,
color and style as the Landlord shall approve; and if any such sign,
advertisement or notice is nevertheless exhibited by the Tenant, the Landlord
shall have the right to remove the same and the Tenant shall be liable for any
and all expenses incurred by the Landlord for said removal. The Landlord shall
have the right to prohibit any advertisement of any Tenant which in the
Landlord's opinion tends to impair the reputation of the Building or its
desirability as a high-quality building for offices for financial, insurance,
legal or other institutions of like nature, and upon written notice from the
Landlord, the Tenant shall immediately refrain from and discontinue any such
advertisement. The Landlord shall have the right to prescribe the weight and
position of safes and other heavy equipment or fixtures, including but not
limited to the rooms and libraries, which shall, if considered necessary by the
Landlord, stand on plank strips to distribute the weight. Any and all damage or
injury to the Demised Premises caused by moving the property of the Tenant into,
in or out of the Demised Premises, or due to the same being on the Demised
Premises, shall be repaired by, and at the sole cost of the Tenant. The Tenant
shall notify the Landlord at least forty-eight (48) hours in advance of any
delivery of furniture, equipment or other bulky matter that requires either
special handling or the use of the service elevator. The Tenant shall provide
its own labor and handling equipment and install masonite or other comparable
material on the carpeting and/or floor of the Common Areas to which such
deliveries are made to prevent damage to the carpets and/or floor. No furniture,
equipment or other bulky matter of any description will be received into the
Demised Premises or carried in the elevators except as approved by the Landlord,
and all such furniture, equipment, and other bulky matter shall be delivered
only through the prescribed delivery entrance and service corridors of the
Building and of the Demised Premises and at times specified by Landlord. All
moving of furniture, equipment and other material shall be during normal
business hours or on such date and time as approved by Landlord and shall be
under the direct control and supervision of the Landlord, but the Landlord shall
not be responsible for any damage to or charges for moving the same. In the
event Tenant requests and Landlord

                                      11
<PAGE>

agrees to moving during other than normal business hours, Tenant shall be
responsible for any additional costs incurred by Landlord, including but not
limited to overtime pay for building staff. The Tenant agrees promptly to remove
any of the Tenant's furniture, equipment or other material delivered or
deposited from the loading dock, walks or areas adjacent to the Demised Premises
or the Building.

     13.  Tenant's Equipment. The Tenant will not install or operate in the
          ------------------
Demised Premises any electrically operated equipment or other machinery other
than printers, servers, typewriters, copiers, personal computers and such other
electrically operated office machinery and equipment normally used in modern
commercial offices without first obtaining the prior written consent of the
Landlord, which consent shall not be unreasonably withheld. The Landlord may
condition such consent upon the payment by the Tenant of additional rent as
compensation for such excess consumption of electricity, utilities or services
as may be occasioned by the operation of said equipment or machinery. The Tenant
shall not install any equipment of any kind or nature whatsoever which will or
may necessitate any changes, replacements or additions to or in the use of the
water system, plumbing system, heating system, air-conditioning system or the
electrical system of the Demised Premises without first obtaining the prior
written consent of the Landlord, which consent shall not be unreasonably
withheld. Business machines or equipment belonging to the Tenant which may cause
noise or vibration that may be transmitted to the Building, or to any space
therein, to such a degree as to be objectionable to the Landlord shall be
installed and maintained on vibration eliminators or other devices sufficient to
eliminate such noise and vibration at the Tenant's expense. In addition, Tenant
agrees to reimburse Landlord for any and all costs relating to updating and/or
modifying architectural drawings deemed reasonably necessary by Landlord to be
made for any such changes, replacements or additions.

     14.  Access. The Tenant will permit the Landlord or its representatives to
          ------
enter the Demised Premises at all reasonable times, without charge therefor to
the Landlord and without diminution of rent payable by the Tenant, to examine,
inspect or to protect the same or prevent damage or injury to the Building, or
to make such alterations and/or repairs or perform such preventative maintenance
as the Landlord may deem necessary, or to exhibit the same to prospective
tenants during the last six (6) months of the term of this Lease.

     The Tenant shall have access to the Demised Premises, lobby and Common
Areas on the floor or floors occupied by it in the building twenty-four (24)
hours a day and seven (7) days a week throughout the year.

     During the course of construction of the Building in which the Demised
Premises shall be located and during the course of construction of improvements
in or to such Demised Premises or Building, the Tenant, its employees, vendors,
consultants, agents and contractors may enter the Demised Premises between the
hours of 7:00 a.m. and 6:00 p.m. on Monday through Friday and 9:00 a.m. and
12:00 noon on Saturday (exclusive of Commonwealth and national holidays which
may be recognized by the Landlord) for the purposes of (a) installing furniture,
fixtures and equipment in the Demised Premises; provided that all such entry is
coordinated with Landlord and Landlord's Contractor upon reasonable advance
notice to Landlord and Landlord's Contractor and (b) inspection of the Demised
Premises only with a representative of Landlord; provided that twenty four (24)
hours written notice in advance be delivered to Landlord or its management
agent. The Tenant agrees that any such entry and inspection shall be at the
Tenant's sole risk and liability.

                                      12
<PAGE>

     15.  Rules and Requlations. The Tenant covenants that the following rules
          ---------------------
and regulations, and such other and further rules and regulations as the
Landlord may make (provided, that such rules and regulations shall not conflict
with the terms, purpose and intent of this Lease or otherwise unreasonably
interfere with the Tenant's intended use of the Demised Premises as office
space) and which in the Landlord's judgment are needful for the general well
being, safety, care and cleanliness of the Demised Premises or the Building of
which they are a part together with their appurtenances, shall be faithfully
kept, observed and performed by the Tenant, and by its agents, servants,
employees and guests, unless waived in writing by the Landlord:

          A.  The Tenant shall not obstruct or use for any purpose other than
     ingress and egress the sidewalks, entries, passages, elevators, public
     corridors and staircases and other parts of the building which are not
     occupied by the Tenant;

          B.  The Tenant shall not install or permit the installation of
     awnings, shades, curtains, draperies and the like other than those approved
     by the Landlord in writing;

          C.  The Tenant shall not place upon any doors of the Demised Premises
     any additional locks or any security system except as may be approved by
     the Landlord in writing, which approval shall not be unreasonably withheld.
     The doors leading to the corridors or main halls shall be kept closed
     during business hours except as they may be used for ingress and egress;

          D.  The Tenant shall not construct, maintain, use or operate within
     the Demised Premises or elsewhere in the Building any equipment or
     machinery which produces music, sound or noise which is audible beyond the
     Demised Premises;

          E.  The Tenant shall not obstruct any electric and telephone floor
     distribution boxes in the Demised Premises;

          F.  The Tenant shall not obstruct or interfere with the rights of
     other tenants, or in any way injure or annoy them or those having business
     with them; and

          G.  The Tenant shall not obstruct building equipment, windows, doors,
     and life safety equipment located in the Building or Demised Premises.

     Notwithstanding the foregoing, Tenant shall not be required to comply with
any rule or regulation of Landlord unless the same applies non-discriminatorily
to all tenants of the Building, does not unreasonably interfere with Tenant's
use of, access to or parking at the Demised Premises, and does not materially
increase the obligations or decrease the rights of Tenant under this Lease.

     Nothing contained in this Lease shall be construed as imposing upon
Landlord any duty or obligation to enforce any such rules and regulations or the
terms, conditions or covenants contained in any other lease, as against any
other tenant, and Landlord shall not be liable to Tenant for the violation of
any such rules or regulations by any other tenant or its employees, agents,
business invitees, licensees, customers, clients, or guests.

     16.  Damage to Demised Premises. If the Demised Premises or Building shall
          --------------------------
be partially damaged by fire or other cause without the fault or neglect of the
Tenant, its agents,

                                      13
<PAGE>

employees or invitees, and if the Demised Premises or Building are so damaged by
fire or other cause to such extent that the damage cannot be fully repaired
within ninety (90) days from the date of such damage, but such damage does not
render the Demised Premises wholly unfit for occupancy the Landlord upon written
notice to the Tenant, may terminate this Lease, in which event the rent shall be
apportioned and paid to the date of such damage. During the period that the
Tenant is deprived of the use of the damaged portion of the Demised Premises,
the Tenant shall be required to pay rent covering only that part of the Demised
Premises that the Tenant is able to occupy and the rent for such space shall be
that portion of the Basic Annual Rent which the amount of square foot area
remaining which can be occupied by the Tenant bears to the total square foot
area of the Demised Premises. In the event of a total or partial destruction of
the Building or Demised Premises by fire or other cause without the fault or
neglect of the Tenant, its agents, employees, or invitees, rendering the Demised
Premises wholly unfit for occupancy, then and in that event, this Lease shall
thereupon cease and terminate and the Tenant shall pay to the Landlord only such
proportionate part of its rent for said premises as has accrued to the date of
such termination.

     All injury or damage to the Demised Premises caused by the Tenant or its
agents, employees and invitees, shall be repaired by the Tenant at the Tenant's
sole expense. If the Tenant shall fail to so do, the Landlord shall have the
right to make such repairs or replacements, and any cost incurred by the
Landlord for such repairs or replacements shall be paid by the Tenant, in which
event such cost shall become additional rent payable within thirty (30) days
after invoice thereof from Landlord. This provision shall be construed as an
additional remedy granted to the Landlord and not in limitation of any other
rights and remedies which the Landlord has or may have in said circumstances.

     17.  Tenant's Property. The Landlord shall not be liable for theft or
          -----------------
misappropriation of property of the Tenant for any reason whatsoever occurring
within the Demised Premises, Building, or parking areas unless caused by or
resulting from the gross negligence of the Landlord, its servants, agents or
employees in the operation or maintenance of the Demised Premises, Building or
parking areas.

     18.  Liability. The Landlord assumes no liability or responsibility
          ---------
whatsoever with respect to the conduct and operation of the business to be
conducted in the Demised Premises. The Landlord shall not be liable for any
accident to or injury to any person or persons or property in or about the
Demised Premises which are caused by the conduct and operation of said business
or by virtue of equipment or property of the Tenant in or about said Demised
Premises. The Tenant hereby agrees to hold the Landlord harmless against all
such claims, expenses (including reasonable attorneys' fees) or judgments
arising by reason of the use of the Demised Premises.

     The Landlord shall not be liable to the Tenant, its employees, agents,
business invitees, licensees, customers, clients, family members, guests or
trespassers for any damage, compensation, costs, expenses (including reasonable
attorneys' fees) or claims arising from the necessity of repairing any portion
of the Demised Premises, the interruption in the use of the Demised Premises,
accident or damage resulting from the use or operation (by the Landlord, the
Tenant, or any other person or persons whatsoever) of elevators, or heating,
cooling, electrical or plumbing equipment or apparatus or any portion of the
Building or Demised Premises or parking areas, or the termination of this Lease
by reason of the total or partial destruction of the Demised Premises, or from
any fire, robbery, theft, and/or any other casualty, or from any leakage into
any part or portion of the Demised Premises, or from water, rain or

                                      14
<PAGE>

snow that may leak into, or flow from, any part of the Demised Premises, or from
drains, pipes or plumbing work in the Demised Premises, or from any other cause
whatsoever. Subject to Paragraph 17 hereof, any goods, property or personal
effects, stored or placed by the Tenant in or about the Demised Premises, the
Building or parking areas shall be at the sole risk of the Tenant and the
Landlord shall not in any manner be held responsible therefor. The employees
and/or contractors of the Landlord are prohibited from receiving any package or
other articles delivered to the Demised Premises for the Tenant, and if any such
employee and/or contractor receives any such package or articles, such employee
and/or contractor shall be the agent of the Tenant for that purpose and not of
the Landlord. The Tenant shall give prompt notice to the Landlord in case of
fire or accident in the Demised Premises, Building or parking area or of any
defects, damage or injury therefrom in any fixtures or equipment of which Tenant
is aware.

     19.  Insurance. Tenant shall maintain with respect to the Demised Premises,
          ---------
commercial general liability insurance, with minimum limits of
$1,000,000/$3,000,000 for personal injury, and $500,000 for property damage.
Tenant shall maintain the insurance coverage required herein with a company or
companies reasonably acceptable to the Landlord. The commercial general
liability insurance policy shall include the Landlord and its agents as
additional named insureds, and will insure Landlord as well as Tenant, against
bodily injury to or death of persons, and against property damage. Tenant shall
deliver certificates of insurance indicating the above-specified coverage to the
Landlord upon the commencement of the term of this Lease, and shall provide
evidence of such coverage annually and as by be reasonably requested by
Landlord. Such insurance policy or policies shall be in a form reasonably
satisfactory to the Landlord, and shall be placed with a company qualified to do
business in Virginia, and shall provide that it (they) cannot be canceled
without at least ten (10) days prior written notice to the Landlord.

     20.  Services. Consistent with the standards observed by operators of first
          --------
class office buildings in the Herndon, Virginia area, the Landlord shall furnish
reasonably adequate electric current, water, lavatory supplies, and
automatically operated elevator service during normal business hours (except
that electrical current shall be supplied to the Demised Premises at all times),
and will provide normal and usual cleaning and char service after business
hours, without additional cost to the Tenant. The Landlord further agrees to
furnish heat and air conditioning during the appropriate seasons of the year
between the hours of 7:00 a.m. and 6:00 p.m. on Monday through Friday and 9:00
a.m. and 12:00 noon on Saturday (exclusive of Commonwealth and national holidays
which may be recognized by the Landlord). However, the Landlord shall not be
liable for any failure to furnish, or for suspension or delays in furnishing,
any of the services described above if caused by breakdown, maintenance or
repair work, or strike, scarcity of labor or materials, riot, civil commotion,
or if due to any cause or reason whatever beyond the control of the Landlord.

     Landlord will (i) make repairs and replacements to HVAC, mechanical, life
safety (including sprinklers), plumbing and electrical systems in or serving the
Demised Premises (to the extent such systems are Building standard) as is
reasonably deemed necessary by Landlord for normal operations of the Building;
(ii) all common areas of the Building, including without limitation the parking
areas; (iii) all structural elements of the Building, including without
limitation the roof, exterior walls, interior bearing walls, foundations,
footings, and all exterior surfaces of the Building (including glass). Landlord
shall perform its obligations under this paragraph in a manner consistent with
other first class office buildings in the Herndon, Virginia submarket.

                                      15
<PAGE>

     21.  Defaults and Remedies. If the Tenant shall fail to pay the rent, or
          ---------------------
any installments thereof as aforesaid, at the time the same shall become due and
payable and/or any additional rent as herein provided and such failure is not
cured within five (5) business days although no demand shall have been made for
the same, or if the Tenant shall violate or fail or neglect to keep and perform
any of the covenants, conditions and agreements herein contained on the part of
the Tenant to be kept and performed and such non-performance continues for
thirty (30) days after notice by Landlord or, if such performance cannot be
reasonably had within such thirty (30) day period, Tenant does not in good faith
commence performance within such thirty (30) day period and diligently proceed
to completion, or if the Demised Premises shall become vacant or deserted for
more than fourteen (14) days, then, and in each and every such event from
thenceforth, and at all times thereafter, at the option of the Landlord, the
Tenant's right of possession shall thereupon cease and terminate, and the
Landlord shall be entitled to the possession of the Demised Premises and to re-
enter the same without demand of possession of the same premises and may
forthwith proceed to recover possession of the demised premises by process of
law, any notice to quit, or of intention to re-enter the same being hereby
expressly waived by the Tenant. In the event of such re-entry by process of law
or otherwise, the Tenant nevertheless agrees to remain answerable for all
damages sustained by the Landlord, including, without limitation, deficiency in
rent, reasonable attorneys' fees, brokerage fees and expense of placing the
Demised Premises in first class rentable condition. And in such case, the
Landlord reserves full power which is hereby acceded to by the Tenant, whether
the keys be returned to the Landlord or its agent and accepted or not, to relet
the said premises for the profit of the Tenant, in liquidation and discharge, in
whole or in part, as the case may be, of the liability of the Tenant under the
terms and provisions of this Lease. And it is further provided that if, under
the provisions hereof, a summons or other applicable summary process shall be
served, and a compromise or settlement thereof shall be made, it shall not be
deemed to be a waiver of any breach of any covenant, condition or agreement
herein contained, or of any subsequent breach thereof. No provision of this
Lease shall be deemed to have been waived by the Landlord unless such waiver
shall be in writing signed by the Landlord. No payment by the Tenant or receipt
by the Landlord of a lesser amount than the monthly installments of rent herein
stipulated shall be deemed to be other than on account of the earliest
stipulated rent nor shall any endorsement of statement on any check or any
letter accompanying any check or payment as rent be deemed an accord and
satisfaction, and the Landlord may accept such check or payment without
prejudice to the Landlord's right to recover the balance of such rent or pursue
any other remedy provided for in this Lease or by law. The provisions contained
in this paragraph shall be in addition to and shall not prevent the enforcement
of any claim the Landlord may have against the Tenant for anticipatory breach of
the unexpired term of this Lease. All rights and remedies of the Landlord under
this Lease shall be cumulative and shall not be exclusive of any other rights
and remedies provided to the Landlord under applicable law.

     22.  Insolvency. If the Tenant or a guarantor of this Lease, if any, shall
          ----------
make an assignment of its assets for the benefit of creditors, of if a receiver
of the assets of the Tenant or any guarantor, if any, is appointed, or if the
Tenant or any guarantor shall commence any case, proceeding or other action
seeking reorganization, arrangement, adjustment, liquidation, dissolution or
composition of its debts under any law, statute or regulation or if an
involuntary petition in any bankruptcy or insolvency proceeding for receivership
be instituted against the Tenant or any guarantor, if any, and the same be not
dismissed within sixty (60) days of the filing thereof, or if the Tenant or any
guarantor, if any, be adjudged bankrupt, then, and in each and every such event,
this Lease shall immediately cease and terminate at the option of the Landlord
with the same force and effect as though the date of said event was the day
herein

                                      16
<PAGE>

fixed for the expiration of the term of this Lease and the Landlord shall be
entitled to immediate possession of the Demised Premises and to recover damages
from the Tenant in accordance with the provisions of Paragraph 21 (Defaults and
Remedies) herein.

     23.  Condemnation. The Tenant agrees that if the whole or a substantial
          ------------
part of the Demised Premises shall be taken or condemned by any competent
authority for public or quasi-public use or purpose, including any sale under
the threat of such a taking, the Tenant shall have no claim against the Landlord
and shall not have any claim or right to any portion of the amount that may be
awarded as damages or paid as a result of any such condemnation or sale; and all
right of the Tenant to damages therefore, if any, are hereby assigned by the
Tenant to the Landlord, except that Tenant may claim and prove in any such
proceeding and receive any award made to Tenant specifically for damages for
loss of movable trade fixtures, equipment and moving expenses so long as such
award does not reduce Landlord's award. And upon such condemnation or taking, or
sale, the term of this Lease shall cease and terminate from the date of such
governmental taking or condemnation or such sale, and the Tenant shall have no
claim against the Landlord for the value of any unexpired term of this Lease.
The rent, however, shall be abated on the date when such title vests in such
governmental authority. If less than a substantial part of the Demised Premises
is taken or condemned by any governmental authority for public or quasi-public
use or purpose (or sale under threat of such taking or condemnation), the rent
shall be equitably adjusted on the date when title vests in such governmental
authority and the Lease shall otherwise continue in full force and effect. For
purposes of this paragraph, a substantial part of the Demised Premises shall be
considered to have been taken if more than thirty percent (30%) of the Demised
Premises are unusable by the Tenant.

     24.  Security Deposit. The Tenant agrees to deposit the Security Deposit
          ----------------
with the Landlord upon execution and delivery of this Lease, to be held by
Landlord without interest, as a security deposit for the full and faithful
performance by the Tenant of each and every term, provision, covenant and
condition of this Lease. In the event that the Tenant defaults in respect of any
of the terms, provisions, covenants and conditions of this Lease, including but
not limited to the payment of rent, the Landlord may use, apply or retain the
whole or any part of the Security Deposit for the payment of any rent in default
or for any other sum which the Landlord may expend or be required to expend by
reason of the Tenant's default, including any damage or deficiency in the re-
letting of any portion of the Demised Premises, whether such damages or
deficiency accrue before or after summary proceedings or other re-entry by the
Landlord. Determination of a default shall be within the sole, complete and
exclusive discretion of the Landlord. The use, application or retention of said
Security Deposit by the Landlord shall not preclude or in any way prohibit the
Landlord from the use of any other remedy or remedies which Landlord may have.

     25.  Holding Over. If the Tenant shall, with the knowledge and written
          ------------
consent of the Landlord, continue to remain in the Demised Premises after the
expiration of the Term of this Lease, then and in that event, the Tenant shall,
by virtue of this Lease, become a tenant by the month at 150% of the rent per
month of the monthly installment of rent agreed by the Tenant to be paid as
aforesaid, commencing said monthly tenancy with the first day next after the end
of the term above demised; and the Tenant shall give to the Landlord at least
thirty (30) days written notice to quit said premises, and the Tenant shall be
entitled to thirty (30) days written notice to quit said premises, except in the
event of nonpayment of rent in advance or the breach of any other covenant by
the Tenant, in which event the Tenant shall not be entitled to any notice to
quit, the usual thirty (30) days written notice to quit being hereby expressly

                                      17
<PAGE>

waived; provided, however, that in the event that the Tenant shall hold over
after the expiration of the term hereby created and if the Landlord shall desire
to regain possession of said premises promptly at the expiration of the term
aforesaid, then at any time prior to the Landlord's acceptance of rent from the
Tenant as a monthly tenant hereunder, the Landlord, at its option, may forthwith
reenter and take possession of said premises without process, or by any legal
process in force.

     26.  Possession. If the Landlord shall be unable to give possession of the
          ----------
Demised Premises on the Lease Commencement Date by reason of the holding over or
retention of possession of any tenant or occupancy, or if repairs, improvements
or decoration of the Demised Premises, or of the Building of which the Demised
Premises form a part, are not completed or for any other reason, the Landlord
shall not be subject to any liability for the failure to give possession on said
date. Under such circumstances, the rent reserved and covenanted to be paid
herein shall not commence until the possession of the Demised Premises is given
or the premises are available for occupancy by the Tenant, and no such failure
to give possession on the Lease Commencement Date shall in any other respect
affect the validity of this Lease or the obligations of the Tenant hereunder,
nor shall the same be construed to extend the Term of this Lease. If permission
is given to the Tenant to enter into the possession of the Demised Premises or
to occupy premises other than the Demised Premises prior to the date specified
as the Lease Commencement Date, the Tenant covenants and agrees that such
occupancy shall be deemed to be under all the terms, covenants, conditions and
provisions of this Lease.

     27.  Ground or Underlying Lease. At the option of any landlord under any
          --------------------------
ground or underlying lease to which this Lease is now or may hereafter become
subject or subordinate, the Tenant agrees that neither the cancellation nor
termination of such ground or underlying lease shall, by operation of law or
otherwise, result in cancellation or termination of this Lease or the
obligations of the Tenant hereunder, and the Tenant covenants and agrees to
attorn to such landlord or to any successor of such Landlord's interest in such
ground or underlying lease, and in that event, this Lease shall continue as a
direct lease between the Tenant herein and such Landlord or its successor; and
in any such case, such Landlord or successor under such ground or underlying
lease shall not be bound by any prepayment on the part of the Tenant or any rent
for more than one month in advance, so that rent shall be payable under this
Lease in accordance with its terms, from the date of the termination of the
ground or underlying lease, as if such prepayment had not been made; and,
provided further, such Landlord or successor under such ground or underlying
lease shall not be bound by this Lease or any amendment or modification of this
Lease unless prior to the termination of such ground or underlying lease, a copy
of this Lease, or amendment of modification thereof, as the case may be, shall
have been delivered to, and accepted by such Landlord or successor.

     28.  Subordination. This Lease is subject and subordinate to all ground or
          -------------
underlying leases and to all mortgages and/or deeds of trust which may now or
hereafter affect such leases or the real property of which the Demised Premises
form a part, and to all renewals, modifications, consolidations, replacements
and extensions thereof. This clause shall be self-operative and no further
instrument of subordination shall be required by any mortgagee or trustee. The
Tenant shall execute promptly any certificate that the Landlord may request to
confirm such subordination. Notwithstanding the foregoing, the party secured by
any such deed of trust or mortgage shall have the right to recognize this Lease,
and in the event of any foreclosure sale under such deed of trust or mortgage,
this Lease shall continue in full force and effect at the option of the party
secured by such deed of trust or mortgage, or the

                                      18
<PAGE>

purchaser under any such foreclosure sale, and the Tenant covenants and agrees
that it will, at the written request of the party secured by any such deed of
trust or mortgage, execute, acknowledge and deliver any instrument that has for
its purpose and effect the subordination of said deed of trust or mortgage to
the lien of this Lease.

     29.  Approval. This Lease shall be subject to and conditioned upon the
          --------
approval of the Landlord's mortgagee, if any, and shall not be deemed final and
effective until written acceptance manifesting said approval is received by the
Landlord, a copy of which will be remitted to the Tenant. The Landlord shall
have thirty (30) days from the date of its execution of this Lease within which
to obtain said approval; otherwise, this condition shall be deemed null and
void.

     30.  Right to Cure Defaults. If the Tenant defaults in the making of any
          ----------------------
payment or in the doing of any act herein required to be made or done by the
Tenant, then the Landlord may, but shall not be required to, make such payment
or do such act, and the amount of the expense thereof, if made or done by the
Landlord, with interest accrued on a daily basis until paid at the Prevailing
Bank Prime Rate from the date payment was due, shall be paid by the Tenant to
the Landlord and shall constitute additional rent hereunder due and payable with
the next monthly installment of rent; but the making of such payment or the
doing of such act by the Landlord shall not operate to cure such default or to
estop the Landlord from the pursuit of any remedy to which the Landlord would
otherwise be entitled. If the Tenant fails to pay any installment of rent on or
before the fifth (5th) business day of the calendar month when such installment
becomes due and payable, the Tenant shall pay to the Landlord a late charge of
five percent (5%) of the amount of such installment, and, in addition, such
unpaid installment shall bear interest at the Prevailing Bank Prime Rate from
five (5) business days after the date such installment became due and payable to
the date of payment thereof by the Tenant. Tenant acknowledges that said late
charge and interest are fair and reasonable. Such late charge and interest shall
constitute additional rent hereunder due and payable immediately.

     31.  Construction Plans. It is agreed that the Tenant will notify Landlord
          ------------------
in writing of its approval of the Construction Plans by not later than March 30,
2000. Construction of any Tenant Improvements will not commence until Tenant
approves the Construction Plans, and all other conditions set forth in Paragraph
6 hereof have been satisfied. In the event the Tenant fails to comply with the
aforesaid by the date specified above, then Landlord may, at its option, at any
time while Tenant is in default of this provision, in addition to any and all
other remedies provided in this Lease, upon not less than ten (10) days written
notice to Tenant, declare this Lease to be terminated and the term ended, in
which event, this Lease shall cease and terminate on the date specified in such
notice with the same force and effect as though the date set forth in such
notice were the date originally set forth herein and fixed for expiration of the
term, and Tenant shall vacate and surrender the Demised Premises.

     32.  Parking. Landlord shall make available to Tenant and its designated
          -------
employees and to Tenant's permitted subtenants parking spaces for the parking of
standard-sized and/or sub-standard sized passenger automobiles in the parking
areas designated for tenants and invitees in a number not to exceed three and
six-tenths (3.6) parking spaces for each 1,000 square feet of space of the
Demised Premises at no additional charge to Tenant during the Term hereof. The
parking areas will be operated on a self-parking basis. In addition, a limited
number of parking spaces will be made available for the parking of invitees of
all the tenants. The Landlord will also make reasonable efforts to have the
parking areas clear and available for use during business hours. A failure to
have the parking areas or access areas clear of snow

                                      19
<PAGE>

or otherwise available for use will not be a breach of the Lease and will not
subject the Landlord to any liability. Subject to Paragraph 17 hereof, the
parking of any car in the parking areas will be at the sole risk of the Tenant,
its employees, agents, invitees and owners of said automobiles.

     Tenant, sub-tenants and employees thereof shall observe reasonable safety
precautions in the use of the parking areas and shall at all times abide by all
rules and regulations promulgated by Landlord governing the use of the parking
areas, which may include, but not be limited to, the requirement that an
identification or parking sticker be displayed at all times on all automobiles
parked in the parking areas. Any automobile not displaying such a sticker, if so
required, or any failure to abide by all rules and regulations promulgated by
Landlord regarding the use of parking areas may necessitate the automobile in
question to be towed away at the car owner's expense.

     33.  Indemnity of Landlord. The Tenant will indemnify and hold harmless the
          ---------------------
Landlord from and against any claim, loss, damage, liability or expense
(including attorneys' fees) occasioned by or resulting from any default
hereunder or any willful or negligent act on the part of the Tenant, its agents,
employees, or invitees, or persons permitted on the Demised Premises by the
Tenant.

     34.  Successors. It is agreed that all rights, remedies and liabilities
          ----------
herein given to or imposed upon either of the parties hereto shall extend to
their respective heirs, executors, administrators, successors and assigns,
except as may be otherwise provided for herein.

     35.  No Partnership. Nothing contained in this Lease shall be deemed or
          --------------
construed to create a partnership or joint venture of or between the Landlord
and the Tenant or to create any other relationship between the parties hereto
other than that of landlord and tenant.

     36.  No Representation by Landlord. Neither the Landlord nor any agent or
          -----------------------------
employee of the Landlord has made any representations or promises with respect
to the Demised Premises except as herein expressly set forth, and no rights,
privileges, easements or licenses are acquired by the Tenant except as herein
expressly set forth. The Tenant, by taking possession of the Demised Premises,
shall accept the same "AS IS", subject to the Punch List and to latent defects,
and other than for Punch List and latent defect items such taking of possession
shall be conclusive evidence that the Demised Premises are in good and
satisfactory condition at the time of such taking of possession.

     37.  Waiver of Jury Trial. The Landlord and the Tenant hereby waive trial
          --------------------
by jury in any action, proceeding or counterclaim brought by either of the
parties hereto against the other on or in respect of any matter whatsoever
arising out of or in any way connected with this Lease, the relationship of
landlord and tenant hereunder, the Tenant's use or occupancy of the Demised
Premises, and/or claim of injury or damage.

     38.  Pronouns. Feminine or neuter pronouns shall be substituted for those
          --------
of the masculine form, and the plural shall be substituted for the singular
number, in any place or places herein in which the context may require such
substitution or substitutions. The Landlord and the Tenant herein for
convenience have been referred to in neuter form.

     39.  Invalidity of Provisions. If any provision of this Lease or the
          ------------------------
application thereof to any persons or circumstances shall to any extent be
invalid or unenforceable, the remainder

                                      20
<PAGE>

of this Lease, or the application of such provision to persons or circumstances
other than those as to which it is invalid or unenforceable, shall not be
affected thereby, and each provision of this Lease shall be valid and be
enforced to the fullest extent permitted by law.

     40.  Governing Law. This Lease shall be governed by and construed in
          -------------
accordance with the laws of the Commonwealth of Virginia.

     41.  Headinqs. Article and section headings are used herein for the
          --------
convenience of reference and shall not be considered when construing or
interpreting this Lease.

     42.  Entire Agreement. This Lease contains and embodies the entire
          ----------------
agreement of the parties hereto and supersedes all prior agreements,
negotiations and discussions between the parties hereto. Any representation,
inducement or agreement that is not contained in this Lease shall not be of any
force or effect. This Lease may not be modified or changed in whole or in part
in any manner other than by an instrument in writing duly signed by all parties
hereto.

     43.  No Offer or Option. The submission of an unsigned copy of this
          ------------------
document to Tenant for Tenant's consideration does not constitute an offer to
lease the premises or an option to or for the premises. This document shall
become effective and binding only upon the execution and delivery of this Lease
by both Tenant and Landlord and, if necessary, any lender.

     44.  Notices. All notices required or desired to be given hereunder by
          -------
either party to the other shall be in writing and given by hand, with evidence
of receipt, or by certified or registered mail. Notices to the respective
parties shall be addressed as follows:

If to the Landlord:      National Rural Utilities
                         Cooperative Finance Corporation
                         Woodland Park
                         2201 Cooperative Way
                         Herndon, Virginia 20171-3025

if to the Tenant:        Inventa Corporation
                         Woodland Park
                         2121 Cooperative Way
                         Suite 100
                         Herndon, Virginia 20171-3025

Either party may by written notice designate a new address to which such notices
shall be directed.

     45.  Special Terms and Conditions. Landlord and Tenant agree to comply with
          ----------------------------
any special terms and conditions identified in Addendum A hereto.

     46.  Time of Essence and Consents. Time is of the essence herein. Except as
          ----------------------------
may be expressly set forth to the contrary: (a) whenever consent or approval of
either party is required, such party shall not unreasonably withhold, condition
or delay such consent or approval; (b) whenever a party is permitted to make a
judgment, form an opinion or exercise discretion in taking any action or making
any determination, the party shall employ commercially reasonable standards in
so doing; and (c) where performance is to be made to a party's satisfaction, an
objective and reasonable standard shall be employed in regard to such
performance.

                                      21
<PAGE>

     IN WITNESS WHEREOF, the said parties have hereunto signed their names and
affixed their seals, on the day and year hereinbefore written.

                                        LANDLORD:

                                        NATIONAL RURAL UTILITIES
WITNESS:                                 COOPERATIVE FINANCE CORPORATION


       /s/ XXX                          By: /s/ XXX
-----------------------------              -------------------------------
Assistant Secretary-Treasurer              Governor Chief Executive Officer

(Seal)

                                        TENANT:

WITNESS:                                INVENTA CORPORATION


       /s/ XXX                          By: /s/ XXX
-----------------------------              -------------------------------
Title:   XXX                            Its:   VP Finance
      -----------------------              -------------------------------


(Seal)

                                      22
<PAGE>

                    ADDENDUM A TO NRTC OFFICE BUILDING LEASE
                    ----------------------------------------

                          Special Terms and Conditions
                          ----------------------------

     1.  Use of Smith-Gill Building Cafeteria. During the Term of this Lease,
         ------------------------------------
Tenant and Tenant's employees and business invitees shall have access to and the
use of the cafeteria located on the first floor of the adjacent Smith-Gill
Building located at 2201 Cooperative Way, Herndon, Virginia, as long as such
cafeteria remains in existence. Under no circumstances shall Landlord be
obligated to continue to maintain or operate the cafeteria located in the Smith-
Gill Building.

     2.  Use of Meeting Rooms in the Building. During the Term of this Lease,
         ------------------------------------
Tenant and Tenant's employees and business invitees shall have access to and the
use of the common area meeting rooms located on the first floor of the Building,
when and if Landlord makes such common area meeting rooms available to tenants
other than National Rural Telecommunications Cooperative and upon such costs,
terms and conditions that Landlord shall determine for tenants at such time.
Under no circumstances shall Landlord be obligated to continue to maintain or
operate the common area meeting rooms located in the Building.

     3.  Repairs. Landlord shall perform and construct, and Tenant shall have no
         -------
responsibility to perform or construct, any repair, maintenance or improvements
(a) necessitated by the acts or omissions of Landlord or any other occupant of
the Building, or their respective agents, employees or contractors, (b)
occasioned by casualty or by the exercise of the power of eminent domain, (c)
for which Landlord has a right of reimbursement from others, (d) which could be
treated as a "capital expenditure" under generally accepted accounting
principles, (e) to the heating, ventilating, air conditioning, electrical,
water, sewer, and plumbing systems serving the Demised Premises and the
Building, and (f) to any portion of the Building outside of the walls of the
Demised Premises; provided, however, that to the extent that any of the
                  --------  -------
foregoing items are Building Operating Expenses as defined in Paragraph 5
hereof, Tenant shall have an obligation to pay its proportionate share thereof
as set forth in Paragraph 5 hereof.

                                      23
<PAGE>

                                   EXHIBIT A

                           [See Attached Floor Plan]
<PAGE>

                                    (Image)
                              Inventa Corporation

                     Architectural Floor Plan, First Floor
<PAGE>

                                   EXHIBIT B

                               Letter of Credit
                               ----------------

[Date]

National Rural Utilities Cooperative
Finance Corporation
2201 Cooperative Way
Herndon, VA 20171

     Re: Irrevocable Standby Letter of Credit
         ------------------------------------

Gentlemen:

     By order of the applicant, Inventa Corporation, we hereby establish our
irrevocable standby Letter of Credit No._____ in your favor for a sum or sums
not to exceed One Hundred Ninety Seven Thousand Seven Hundred Seven and 50/100
Dollars ($197,707.50) (U.S. Dollars)in the aggregate, effective immediately.

     This Letter of Credit shall be payable in immediately available funds in
U.S. Dollars. Funds under this Letter of Credit are payable to you upon your
presentation to us of the original of this Letter of Credit and a sight draft
drawn on us in the form attached as Annex 1 hereto. All drafts must be marked:
"Drawn under Letter of Credit No.____ of [Name of Issuing Bank]."
                                         ----------------------

     This Letter of Credit shall expire twelve months from the date hereof; but
is automatically extendable, so that this Letter of Credit shall be deemed
automatically extended, from time to time, without amendment, for one year from
the expiration date hereof and from each and every future expiration date,
unless at least sixty (60) days prior to any expiration date we shall notify you
by certified or registered mail that we elect not to consider this Letter of
Credit renewed for any such additional period. The final expiration date hereof
shall be no earlier than [fill in date which is 90 days after expiration of
                         --------------------------------------------------
lease].
------

     This Letter of Credit is transferable and may be transferred one or more
times. However, no transfer shall be effective unless advice of such transfer is
received by us in our standard form.

     We hereby agree to honor each draft drawn under and in compliance with this
letter of credit, if duly presented at our offices at ________, or at any other
of our offices in ______.

     This Letter of Credit is subject to the International Standby Practices
1998, International Chamber of Commerce Publication No. 590.

                            [Name of Issuing Bank]

                            By:____________________________

                            Its:___________________________
<PAGE>

                                                                         ANNEX 1

                              Form of Sight Draft
                              -------------------

                Drawn under Irrevocable Standby Letter of Credit
                       No.___ of [Name of Issuing Bank]

                                    [Date]

[Name and Address of Issuing Bank]

Ladies and Gentlemen:

     PAY AT SIGHT to the order of National Rural Utilities Cooperative Finance
Corporation the sum of $__________.

                              NATIONAL RURAL UTILITIES
                              COOPERATIVE FINANCE CORPORATION

                              By:____________________________
                              Name:__________________________
                              Title:_________________________
<PAGE>

                      [LETTERHEAD OF SILICON VALLEY BANK]
                            International Division



IRREVOCABLE STANDBY LETTER OF CREDIT NO. SVB00IS2114

DATE: FEBRUARY 14, 2000

BENEFICIARY:
NATIONAL RURAL UTILITIES COOPERATIVE
FINANCE CORPORATION
2201 COOPERATIVE WAY
HERNDON, VA 20171
AS "LANDLORD"

APPLICANT:
INVENTA CORPORATION
255 SHORELINE DRIVE, 2/ND/ FLOOR
REDWOOD SHORES, CA 94065
AS "TENANT"

AMOUNT: US$197,707.50 (ONE HUNDRED NINETY SEVEN THOUSAND SEVEN HUNDRED
SEVEN AND 50/100 U.S. DOLLARS)

EXPIRATION DATE: FEBRUARY 10, 2001

LOCATION: AT OUR COUNTERS IN SANTA CLARA, CALIFORNIA

DEAR SIR/MADAM:

WE HEREBY ESTABLISH OUR IRREVOCABLE STANDBY LETTER OF CREDIT NO. SVB00IS2114 IN
YOUR FAVOR AVAILABLE BY YOUR DRAFTS DRAWN ON US AT SIGHT AND ACCOMPANIED BY THE
FOLLOWING DOCUMENTS:

1. THE ORIGINAL OF THIS LETTER OF CREDIT AND ALL AMENDMENT(S), IF ANY.

PARTIAL DRAWS ARE ALLOWED. THIS LETTER OF CREDIT MUST ACCOMPANY ANY DRAWINGS
HEREUNDER FOR ENDORSEMENT OF THE DRAWING AMOUNT AND WILL BE RETURNED TO THE
BENEFICIARY UNLESS IT IS FULLY UTILIZED.

THIS LETTER OF CREDIT SHALL BE AUTOMATICALLY EXTENDED FOR AN ADDITIONAL PERIOD
OF ONE YEAR, WITHOUT AMENDMENT, FROM THE PRESENT OR EACH FUTURE EXPIRATION DATE
BUT IN ANY EVENT NOT BEYOND AUGUST 1, 2005 WHICH SHALL BE THE FINAL EXPIRATION
DATE OF THIS LETTER OF CREDIT, UNLESS, AT LEAST SIXTY (60) DAYS PRIOR TO THE
THEN CURRENT EXPIRATION DATE WE NOTIFY YOU BY REGISTERED MAIL/OVERNIGHT COURIER
SERVICE AT THE ABOVE ADDRESS THAT THIS LETTER OF CREDIT WILL NOT BE EXTENDED
BEYOND THE CURRENT EXPIRATION DATE.

                                  Page 1 of 2
<PAGE>

                     [LETTERHEAD OF SILICON VALLEY BANK]]
                            International Division


IRREVOCABLE STANDBY LETTER OF CREDIT NO. SVB00IS2114

DATE: FEBRUARY 14, 2000

THIS LETTER OF CREDIT MAY BE TRANSFERRED IN ITS ENTIRETY MORE THAN ONCE BY THE
ISSUING BANK UPON OUR RECEIPT OF THE ATTACHEDEXHIBIT "A" DULY COMPLETED AND
EXECUTED BY THE BENEFICIARY AND ACCOMPANIED BY THE ORIGINAL LETTER OF CREDIT AND
ALL AMENDMENT(S), IF ANY, TOGETHER WITH THE PAYMENT OF OUR TRANSFER FEE OF  1/4
OF 1% OF THE TRANSFER AMOUNT (MINIMUM USD250.00).

DRAFT(S) AND DOCUMENTS MUST INDICATE THE NUMBER AND DATE OF THIS LETTER OF
CREDIT.

DOCUMENTS MUST BE FORWARDED TO US BY OVERNIGHT DELIVERY SERVICE TO: SILICON
VALLEY BANK. 3003 TASMAN DRIVE, SANTA CLARA CA 95054, ATTN: INTERNATIONAL
DIVISION.

WE HEREBY AGREE WITH THE DRAWERS, ENDORSERS AND BONAFIDE HOLDERS THAT THE DRAFTS
DRAWN UNDER AND IN ACCORDANCE WITH THE TERMS AND CONDITIONS OF THIS LETTER OF
CREDIT SHALL BE DULY HONORED UPON PRESENTATION TO THE DRAWEE, IF NEGOTIATED ON
OR BEFORE THE EXPIRATION DATE OF THIS CREDIT.

THIS LETTER OF CREDIT IS SUBJECT TO THE UNIFORM CUSTOMS AND PRACTICE FOR
DOCUMENTARY CREDITS (1993 REVISION), INTERNATIONAL CHAMBER OF COMMERCE
PUBLICATION 500.



       /s/ XXX                          /s/ XXX
----------------------------      --------------------------
 AUTHORIZED SIGNATURE              AUTHORIZED SIGNATURE

                                  Page 2 of 2
<PAGE>

                      [LETTERHEAD OF SILICON VALLEY BANK]
                            International Division


                                  EXHIBIT "A"

DATE:

TO: SILICON VALLEY BANK
  3003 TASMAN DRIVE                     RE:  STANDBY LETTER OF CREDIT
  SANTA CLARA, CA 95054                      NO. SVB00IS2114 ISSUED BY
  ATTN: INTERNATIONAL DIVISION.              SILICON VALLEY BANK, SANTA CLARA
       STANDBY LETTERS OF CREDIT             L/C AMOUNT:

GENTLEMEN:

FOR VALUE RECEIVED, THE UNDERSIGNED BENEFICIARY HEREBY IRREVOCABLY TRANSFERS TO:

(NAME OF TRANSFEREE)
(ADDRESS)

ALL RIGHTS OF THE UNDERSIGNED BENEFICIARY TO DRAW UNDER THE ABOVE LETTER OF
CREDIT UP TO ITS AVAILABLE AMOUNT AS SHOWN ABOVE AS OF THE DATE OF THIS
TRANSFER.

BY THIS TRANSFER, ALL RIGHTS OF THE UNDERSIGNED BENEFICIARY IN SUCH LETTER OF
CREDIT ARE TRANSFERRED TO THE TRANSFEREE. TRANSFEREE SHALL HAVE THE SOLE RIGHTS
AS BENEFICIARY THEREOF, INCLUDING SOLE RIGHTS RELATING TO ANY AMENDMENTS,
WHETHER INCREASES OR EXTENSIONS OR OTHER AMENDMENTS, AND WHETHER NOW EXISTING OR
HEREAFTER MADE. ALL AMENDMENTS ARE TO BE ADVISED DIRECT TO THE TRANSFEREE
WITHOUT NECESSITY OF ANY CONSENT OF OR NOTICE TO THE UNDERSIGNED BENEFICIARY.

THE ORIGINAL OF SUCH LETTER OF CREDIT IS RETURNED HEREWITH, AND WE ASK YOU TO
ENDORSE THE TRANSFER ON THE REVERSE THEREOF, AND FORWARD IT DIRECTLY TO THE
TRANSFEREE WITH YOUR CUSTOMARY NOTICE OF TRANSFER.

SINCERELY,

_________________________________
  (BENEFICIARY'S NAME)

_________________________________
SIGNATURE OF BENEFICIARY


SIGNATURE AUTHENTICATED


_________________________________
  (NAME OF BANK)


_________________________________
 AUTHORIZED SIGNATURE
<PAGE>

                      [LETTERHEAD OF SILICON VALLEY BANK]
                            International Division


IRREVOCABLE STANDBY LETTER OF CREDIT NO. SVB00IS2114

DATE:  FEBRUARY 14, 2000

BENEFICIARY:
NATIONAL RURAL UTILITIES COOPERATIVE
FINANCE CORPORATION
2201 COOPERATIVE WAY
HERNDON, VA 20171
AS "LANDLORD"

APPLICANT:
INVENTA CORPORATION
255 SHORELINE DRIVE, 2/ND/ FLOOR
REDWOOD SHORES, CA 94065
AS "TENANT"

AMOUNT: US$197,707.50 (ONE HUNDRED NINETY SEVEN THOUSAND SEVEN HUNDRED
SEVEN AND 50/100 U.S. DOLLARS)

EXPIRATION DATE: FEBRUARY 10, 2001

LOCATION: AT OUR COUNTERS IN SANTA CLARA, CALIFORNIA

DEAR SIR/MADAM:

WE HEREBY ESTABLISH OUR IRREVOCABLE STANDBY LETTER OF CREDIT NO. SVB00IS2114 IN
YOUR FAVOR AVAILABLE BY YOUR DRAFTS DRAWN ON US AT SIGHT AND ACCOMPANIED BY THE
FOLLOWING DOCUMENTS:

1. THE ORIGINAL OF THIS LETTER OF CREDIT AND ALL AMENDMENT(S), IF ANY.

PARTIAL DRAWS ARE ALLOWED. THIS LETTER OF CREDIT MUST ACCOMPANY ANY DRAWINGS
HEREUNDER FOR ENDORSEMENT OF THE DRAWING AMOUNT AND WILL BE RETURNED TO THE
BENEFICIARY UNLESS IT IS FULLY UTILIZED.

THIS LETTER OF CREDIT SHALL BE AUTOMATICALLY EXTENDED FOR AN ADDITIONAL PERIOD
OF ONE YEAR, WITHOUT AMENDMENT, FROM THE PRESENT OR EACH FUTURE EXPIRATION DATE
BUT IN ANY EVENT NOT BEYOND AUGUST 1, 2005 WHICH SHALL BE THE FINAL EXPIRATION
DATE OF THIS LETTER OF CREDIT, UNLESS, AT LEAST SIXTY (60) DAYS PRIOR TO THE
THEN CURRENT EXPIRATION DATE WE NOTIFY YOU BY REGISTERED MAIL/OVERNIGHT COURIER
SERVICE AT THE ABOVE ADDRESS THAT THIS LETTER OF CREDIT WILL NOT BE EXTENDED
BEYOND THE CURRENT EXPIRATION DATE.

                                  Page 1 of 2
<PAGE>

                       LETTERHEAD OF SILICON VALLEY BANK
                            International Division


IRREVOCABLE STANDBY LETTER OF CREDIT NO. SVB00IS2114

DATE: FEBRUARY 14, 2000

THIS LETTER OF CREDIT MAY BE TRANSFERRED IN ITS ENTIRETY MORE THAN ONCE BY THE
ISSUING BANK UPON OUR RECEIPT OF THE ATTACHED EXHIBIT "A" DULY COMPLETED AND
EXECUTED BY THE BENEFICIARY AND ACCOMPANIED BY THE ORIGINAL LETTER OF CREDIT AND
ALL AMENDMENT(S), IF ANY, TOGETHER WITH THE PAYMENT OF OUR TRANSFER FEE OF  1/4
OF 1% OF THE TRANSFER AMOUNT (MINIMUM USD250.00).

DRAFT(S) AND DOCUMENTS MUST INDICATE THE NUMBER AND DATE OF THIS LETTER OF
CREDIT.

DOCUMENTS MUST BE FORWARDED TO US BY OVERNIGHT DELIVERY SERVICE TO: SILICON
VALLEY BANK. 3003 TASMAN DRIVE, SANTA CLARA CA 95054, ATTN: INTERNATIONAL
DIVISION.

WE HEREBY AGREE WITH THE DRAWERS, ENDORSERS AND BONAFIDE HOLDERS THAT THE DRAFTS
DRAWN UNDER AND IN ACCORDANCE WITH THE TERMS AND CONDITIONS OF THIS LETTER OF
CREDIT SHALL BE DULY HONORED UPON PRESENTATION TO THE DRAWEE, IF NEGOTIATED ON
OR BEFORE THE EXPIRATION DATE OF THIS CREDIT.

THIS LETTER OF CREDIT IS SUBJECT TO THE UNIFORM CUSTOMS AND PRACTICE FOR
DOCUMENTARY CREDITS (1993 REVISION), INTERNATIONAL CHAMBER OF COMMERCE
PUBLICATION 500.


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 AUTHORIZED SIGNATURE                    AUTHORIZED SIGNATURE

                                  Page 2 of 2
<PAGE>

                      [LETTERHEAD OF SILICON VALLEY BANK]
                            International Division

                                  EXHIBIT "A"

DATE:

TO: SILICON VALLEY BANK
 3003 TASMAN DRIVE                        RE:  STANDBY LETTER OF CREDIT
 SANTA CLARA, CA 95054                         NO. SVB00IS2114 ISSUED BY
 ATTN: INTERNATIONAL DIVISION.                 SILICON VALLEY BANK, SANTA CLARA
 STANDBY LETTERS OF CREDIT                     L/C AMOUNT:

GENTLEMEN:

FOR VALUE RECEIVED, THE UNDERSIGNED BENEFICIARY HEREBY IRREVOCABLY TRANSFERS TO:

(NAME OF TRANSFEREE)
(ADDRESS)

ALL RIGHTS OF THE UNDERSIGNED BENEFICIARY TO DRAW UNDER THE ABOVE LETTER OF
CREDIT UP TO ITS AVAILABLE AMOUNT AS SHOWN ABOVE AS OF THE DATE OF THIS
TRANSFER.

BY THIS TRANSFER, ALL RIGHTS OF THE UNDERSIGNED BENEFICIARY IN SUCH LETTER OF
CREDIT ARE TRANSFERRED TO THE TRANSFEREE. TRANSFEREE SHALL HAVE THE SOLE RIGHTS
AS BENEFICIARY THEREOF, INCLUDING SOLE RIGHTS RELATING TO ANY AMENDMENTS,
WHETHER INCREASES OR EXTENSIONS OR OTHER AMENDMENTS, AND WHETHER NOW EXISTING OR
HEREAFTER MADE. ALL AMENDMENTS ARE TO BE ADVISED DIRECT TO THE TRANSFEREE
WITHOUT NECESSITY OF ANY CONSENT OF OR NOTICE TO THE UNDERSIGNED BENEFICIARY.

THE ORIGINAL OF SUCH LETTER OF CREDIT IS RETURNED HEREWITH, AND WE ASK YOU TO
ENDORSE THE TRANSFER ON THE REVERSE THEREOF, AND FORWARD IT DIRECTLY TO THE
TRANSFEREE WITH YOUR CUSTOMARY NOTICE OF TRANSFER.

SINCERELY,


______________________________
  (BENEFICIARY'S NAME)


______________________________
SIGNATURE OF BENEFICIARY


SIGNATURE AUTHENTICATED


______________________________
  (NAME OF BANK)


______________________________
 AUTHORIZED SIGNATURE