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                                                                    EXHIBIT 10.8

                              AGREEMENT OF SUBLEASE

         This Agreement of Sublease (this "Sublease") is made as of the 17th day
of March, 2000 by and between RENAISSANCE WORLDWIDE, INC., a Massachusetts
corporation, having an office at 52 Second Avenue, Waltham, Massachusetts 02451
("Sublessor"), and SITARA NETWORKS, INC., a Delaware corporation, having an
office at 52 Second Avenue, Waltham, Massachusetts 02451 ("Sublessee").

                                   WITNESSETH

         WHEREAS, by a certain Lease Agreement, dated as of June 30, 1998 (the
"Lease"), by and between Waltham 60/10 LLC ("Landlord"), as landlord, and
Sublessor, as tenant, Landlord leased to Sublessor certain premises consisting
of approximately 201,378 rentable square feet (the "Premises"), being all of the
rentable area in that certain building known as and numbered 52 Second Avenue,
Waltham, Massachusetts (the "Building"), which Premises are more particularly
described in the Lease, a copy of which Lease is annexed hereto as Exhibit A and
made a part hereof; and

         WHEREAS, Sublessee desires to sublease from Sublessor and Sublessor is
willing to sublease to Sublessee a portion of the Premises consisting of
approximately one-half of the second floor of the Building, containing
approximately 25,889 rentable square feet as more particularly shown on Exhibit
B annexed hereto and made a part hereof (the "Subleased Premises");

         NOW THEREFORE, in consideration of Ten Dollars ($ 10) in hand paid by
Sublessee to Sublessor, the mutual covenants herein contained and for other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto hereby agree as follows:

         1. Subleasing of Subleased Premises; Condition of Premises.

         (1) Sublessor hereby subleases to Sublessee and Sublessee hereby hires
from Sublessor, the Subleased Premises, upon and subject to all of the terms,
covenants, rentals and conditions hereinafter set forth. Sublessee expressly
acknowledges and agrees that Sublessor has made no representations with respect
to the Subleased Premises or the Building and is not obligated to make repairs
of or to perform any work at, the Subleased Premises, except as set forth
elsewhere in this Sublease.
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         (2) The Subleased Premises, containing approximately 25,889 rentable
square feet, as more particularly shown on Exhibit B attached hereto and made a
part hereof, is currently unfinished "shell" space. Sublessee and Sublessor have
agreed upon the layout/partitioning plan for the Subleased Premises, which
layout/partitioning plan is shown on Exhibit B. Sublessor shall, at Sublessor's
sole cost and expense, cause the Subleased Premises to be built out in
accordance with Exhibit B to a kind and quality of construction consistent with
that of the balance of the second floor, excluding any non-standard
improvements, including, but not limited to, any labs, special electrical (such
as any work to equip an office or cubicle for more than one computer),
mechanical or plumbing requirements, and all tel/data cabling. The net
additional costs and expenses of all such non-standard improvements, as well as
of any changes or additions to the plan on Exhibit B and of any delays caused by
such changes or additions, by Sublessee's failure to promptly respond to
Sublessor requests for approvals or consents or by any other act or negligence
of Sublessee or Sublessee's agents, contractors or employees ("Sublessee
Delays") shall be payable as Additional Rent by Sublessee to Sublessor upon
demand. Any such demand shall be accompanied by copies of contracts, paid
invoices or other suitable evidence of Sublessor's payment thereof or obligation
therefor. Sublessee also acknowledges and agrees that it is obligated at its
sole cost and expense to restore the Subleased Premises prior to the end of the
Term to general office use substantially in accordance with Exhibit C attached
hereto and made a part hereof, including, without limitation, the restoration of
each circled and checked area of the plan on Exhibit C in accordance with the
plan on Exhibit C. Such cost and expense shall be deemed Additional Rent. The
Commencement Date referred to in Section 2 below shall mean the earlier of (i)
such date as Sublessor delivers the Subleased Premises to Sublessee
substantially complete and suitable for Sublessee's use and occupancy but not in
any event prior to June 10, 2000 (such suitability shall be evidenced by a
certificate of occupancy and the architect's certificate of substantial
completion); (ii) such date as Sublessee takes occupancy of any portion of the
Subleased Premises for business purposes; or (iii) such date (after June 10,
2000) as the Subleased Premises would have been substantially complete but for a
delay in the build-out attributable to any change, addition or non-standard
improvement to the plan in Exhibit B requested by Sublessee or to other
Sublessee Delays as aforesaid. Notwithstanding the foregoing, Sublessee shall
have the right, so long as the same does not materially adversely affect the
progress or completion of Sublessor's work therein, to have access to the
Subleased Premises at least two weeks prior to such substantial completion date
(which Sublessor shall provide notice thereof) for the purpose of installing
Sublessee's furnishings and equipment, without such access being deemed to be
occupancy for Sublessee's business purposes. In the event that the Subleased
Premises are not substantially complete within ninety (90) days after June 10,
2000, as extended for all such Sublessee Delays and by any delays caused by
force majeure, which shall include strikes, inability to obtain materials,
casualties and other matters beyond Sublessor's reasonable control, then
Sublessee may terminate this Sublease by providing written notice to Sublessor
prior to such substantial completion. Sublessor shall use commercially
reasonable efforts to have the Subleased Premises substantially complete by June
10, 2000, as extended by any Sublessee Delays and by any delays caused by force
majeure, which shall include strikes, inability to obtain materials, casualties
and other matters beyond Sublessor's reasonable control.

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         (3) Notwithstanding anything to the contrary herein (i) the Subleased
Premises shall not include, and Sublessor expressly reserves the exclusive use
of (including continuous access to and from), Telephone Closet No. 2117; (ii)
Sublessor and Sublessee shall share appropriate usage of Telephone Closet No.
203; and (iii) Sublessee shall provide its own reception functions within the
Subleased Premises, and shall not have any right to representation
at/participation in Sublessor's reception on the first office level of the
Building.

         2. Term.

         The term (the "Term") of this Sublease shall commence on the
Commencement Date and shall expire at 11:59 p.m. on the last day of the calendar
month in which occurs the expiration of three (3) years from the Commencement
Date (the "Expiration Date"), unless sooner extended or terminated as
hereinafter provided.

         3. Fixed Rent.

         (1) For the period commencing on the Commencement Date, Sublessee shall
pay to Sublessor, in lawful money of the United States, a Fixed Rent at the rate
of eight hundred sixty-seven thousand two hundred eighty-one and 50/100 dollars
($867,281.50) per annum ($72,273.46 per month). Concurrently with the execution
of this Sublease, Sublessee shall deliver to Sublessor the first month's rent in
the amount of $72,273.46. For any partial month at the beginning of the Term,
Fixed Rent shall be appropriately prorated.

         (2) Fixed Rent shall be due and payable on the first (1st) day of each
calendar month during the Term at the office of Sublessor, or at such other
place as Sublessor may designate, at any time from time to time, without any
set-off or deduction of any kind whatsoever, except that Sublessee shall pay to
Sublessor the first monthly installment of Fixed Rent due under this Sublease
(together with such electricity charges as shall be due in accordance with
Section 23 of this Sublease), upon the execution of this Sublease.

         4. Additional Rent.

         (1) Beginning with the payment of Fixed Rent due for the 13th full
calendar month of the Term, Sublessee shall pay to Sublessor, as Additional
Rent, Sublessee's Proportionate Share, as hereinafter defined, of such amounts
as Sublessor from time to time gives notice to Sublessee that Sublessor is
obligated to pay to Landlord in respect of Operating Costs, including estimated
payments thereof, under and pursuant to Section 4.2 of the Lease, but only to
the extent such payments on an annualized basis, exceed, or are reasonably
estimated by Sublessor to exceed, $9.50 per rentable square foot per year.
Sublessee shall be entitled to Sublessee's Proportionate Share of any credit or
refund as and when received by Sublessor, and shall pay Sublessee's

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Proportionate Share of any additional payment required to be made by Sublessor,
as a result of the final determination of Operating Costs for any calendar year
as provided in Section 4.2 of the Lease to the extent the same exceeds $9.50 per
rentable square foot. Sublessee's Proportionate share shall be a fraction, the
numerator of which is the rentable square feet in the Subleased Premises and the
denominator of which is the rentable square feet in the Premises, currently
25,889/201,378 or 12.86%.

         (2) All amounts payable by Sublessee to Sublessor pursuant to this
Sublease, including, without limitation, Fixed Rent and Additional Rent, shall
be deemed to be and shall constitute rent for all purposes hereunder and, in the
event of any non-payment thereof, Sublessor shall have all of the rights and
remedies provided herein (including, without limitation, those rights and
remedies set forth in Section 10 hereof), at law or in equity for non-payment of
rent. The obligation of Sublessee to pay all amounts to Sublessor of Fixed Rent
and Additional Rent due hereunder, as well as any refund which may be due to
Sublessee hereunder, and of other amounts payable by Sublessor to Sublessor
under the Lease, as and to the extent incorporated herein and as modified
hereby, shall survive the Expiration Date or earlier termination of this
Sublease.

         5. Care, Surrender and Restoration of the Subleased Premises.

         (1) Without limiting any other provision of this Sublease or the Lease,
Sublessee shall take good care of the Subleased Premises, suffer no waste or
injury thereto and shall comply with all laws, orders and regulations applicable
to the Subleased Premises, the Building and Sublessee's use or manner of use
thereof, which are imposed on Sublessor, as tenant under the Lease, in
connection with the Subleased Premises and/or the Building; provided Sublessee
is given copies of any rules and regulations applicable to the Building; and
provided further that Sublessee shall have no obligation to make or pay for
alterations to the Subleased Premises that would be required for any office use,
as distinct from Sublessee's particular use thereof. Notwithstanding the first
paragraph of Section 6.1 of the Lease, Sublessee shall make no Alteration (as
defined in Article 6 of the Lease) to the Subleased Premises without the prior
written consent of Sublessor, and then only fully in compliance with the
applicable provisions of Article 6 of the Lease. In no event, however, shall
Sublessee have any right with respect to the elevator and atrium lobby area of
the Subleased Premises either (i) to make any Alteration, addition,
modification, decoration or fixturing, or (ii) to use it for any Sublessee
purpose whatsoever, except as set-forth herein.

         (2) Upon the Expiration Date or earlier termination of the Term,
Sublessee shall quit and surrender the Subleased Premises to Sublessor, broom
clean, in good order and condition, ordinary wear and tear excepted and
Sublessee shall remove all of its personal property therefrom. If the Expiration
Date or earlier termination of the Term falls on a Sunday, this Sublease shall
expire at noon on the immediately preceding Saturday unless such Saturday is a
legal holiday, in which case the Term shall expire at noon on the first business
day immediately

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preceding such Saturday. Sublessee shall observe and perform each of the
covenants contained in this Sublease and Sublessee's obligations hereunder shall
survive the Expiration Date or earlier termination of this Sublease, but only to
the extent provided herein or incorporated by reference from the Lease.

         6. Use.

         Sublessee shall use and occupy the Subleased Premises as and for office
use and for no other purpose. Sublessee shall have access to the Subleased
Premises 24 hours a day, seven days a week, subject to Sublessor's usual
security measures and subject also to fire, casualty, emergency repairs and
other such matters beyond Sublessor's reasonable control.

         7. Subordination to and Incorporation of Terms of the Lease.

         (1) This Sublease is in all respects subject and subordinate to all of
the terms, provisions, covenants, stipulations, conditions and agreements of the
Lease, and, except as otherwise expressly provided in this Sublease, all of the
terms, provisions, covenants, stipulations, conditions, rights, obligations,
remedies and agreements of the Lease (including but not limited to Article 14
(except for Section 14.3) of the Lease as to payment of Fixed Rent and
Additional Rent in accordance with the provisions hereof) are incorporated in
this Sublease by reference and made a part hereof as if herein set forth at
length, and shall, as between Sublessor and Sublessee (as if they were the
Landlord and Tenant, respectively, under the Lease, and the word "Lease" were
"Sublease" and the word "Premises" were "Subleased Premises"), constitute the
terms of this Sublease, except for Articles 2, 3, 4 and 5 (except Section 5.3),
Section 7.1, Article 9, Sections 14.2 (e), 14.3, 15.1, 16.1 and 16.3, Articles
17, 18, 19 and 20 and Sections 21.2, 21.6, 21.9 and 21.10, as well as such other
terms of the Lease as do not relate to the Subleased Premises or are
inapplicable to, inconsistent with, or specifically modified by, the terms of
this Sublease (which provisions, for purposes of this Sublease, are hereby
deemed deleted in their entirety). In furtherance of the foregoing, Sublessee
shall not take any action or do or permit to be done anything which (i) is or
may be prohibited to Sublessor, as tenant under the Lease, (ii) might result in
a violation of or default under any of the terms, covenants, conditions or
provisions of the Lease or any other instrument to which this Sublease is
subordinate, or (iii) would result in any additional cost or other liability to
Sublessor. This clause shall be self-operative and no further instrument of
subordination shall be required, but Sublessee shall execute promptly any
certificate confirming such subordination that Sublessor may request. In the
event of any inconsistency between this Sublease and the Lease, such
inconsistency shall be resolved in favor of that obligation which is more
onerous to Sublessee or that restriction which is more restrictive of Sublessee,
as the case may be.

         (2) In the event that the Lease is canceled or terminated, Sublessee
shall, at the option of Landlord, attorn to and recognize Landlord, as Sublessor
hereunder, and shall, promptly upon

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Landlord's request, execute and deliver all instruments necessary or appropriate
to confirm such attornment and recognition. Sublessee hereby waives all rights
under any present or future law to elect, by reason by the termination of the
Lease, to terminate this Sublease or surrender possession of the Subleased
Premises.

         8. Sublessee's Obligations.

         Except as specifically set forth herein to the contrary, all acts to be
performed by, and all of the terms, provisions, covenants, stipulations,
conditions, obligations and agreements to be observed by, Sublessor, as tenant
under the Lease, shall, to the extent that the same relate to the Subleased
Premises, be performed and observed by Sublessee, and Sublessee's obligations in
respect thereof shall run to Sublessor or Landlord, as Sublessor may determine
to be appropriate or as may be required by the respective interests of Sublessor
and Landlord. Notwithstanding the foregoing, nothing in this Article 8 shall be
deemed to expand the terms, provisions, covenants, stipulations, conditions,
obligations and agreements of Sublessee beyond those set forth in this Sublease
or in the Lease, as and to the extent incorporated herein, as modified hereby.
Sublessee shall indemnify, defend and hold Sublessor harmless from and against
all liabilities, losses, obligations, damages, penalties, claims, costs and
expenses (including, without limitation, attorneys' fees and other costs) which
are paid, suffered or incurred by Sublessor or claimed or asserted against
Sublessor as a result of the nonperformance or nonobservance of any such terms,
provisions, covenants, stipulations, conditions, obligations or agreements by
Sublessee hereunder.

         9. Sublessor's Obligations.

         Sublessor agrees that except as expressly provided herein, Sublessee
shall have and enjoy the same rights which Sublessor, as tenant under the Lease,
has to performance by Landlord of any service, repair, alteration or other
similar obligation which is the obligation of Landlord to perform under those
provisions of the Lease incorporated herein, provided, however, that
notwithstanding anything contained in this Sublease to the contrary, Sublessor
shall have no responsibility to Sublessee for, and shall not be required to
provide, any of the services or make any of the repairs or restorations which
Landlord has agreed to make or provide, or cause to be made or provided, under
the Lease (including, without limitation, Landlord's obligations set forth in
Article 5 of the Lease) and Sublessee shall rely upon, and look solely to,
Landlord for the provision of such services and the performance of such repairs
and restorations. Sublessor agrees to use reasonable efforts to cooperate in
assisting Sublessee to obtain such repairs from Landlord, if requested. In no
event shall Sublessor have any obligation to bring any action or proceeding or
to take any steps to enforce Sublessor's rights against Landlord. Sublessee
shall contact Sublessor's facility manager, Spaulding & Slye Colliers (or such
other person or entity as Sublessor shall from time to time identify as its
facility manager by notice to Sublessee), for all Building concerns such as
maintenance, janitorial, cafeteria, fitness center, parking, security and other
Building related issues. Sublessee shall not make any claim against Sublessor
for any

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damage which may result from, nor shall Sublessee's obligations hereunder
(including, without limitation, Sublessee's obligation to pay all Fixed Rent and
Additional Rent when due) be impaired by reason of (a) the failure of Landlord
to keep, observe or perform any of its obligations under the Lease, or (b) the
acts or omissions of Landlord or any of its agents, contractors, servants,
employees, invitees or licensees. If Landlord shall default in any of its
obligations to Sublessor with respect to the Subleased Premises, Sublessee shall
be entitled to request that Sublessor enforce Sublessor's rights against
Landlord with respect thereto, but Sublessor shall have no obligation to bring
any action or proceeding or to take any steps to enforce Sublessor's rights
against Landlord. In the event of such default and in the event that Sublessor
elects a remedy that entitles Sublessor to rent abatement and Sublessor receives
such abatement, then Sublessor agrees, to pass on to Sublessee a share of such
abatement to the extent it applies to the Subleased Premises.

         10. Covenants with Respect to the Lease.

         In the event that Sublessee shall be in default of any term, provision,
covenant, stipulation, condition, obligation or agreement of, or shall fail to
honor any obligation under, this Sublease, Sublessor, on giving the notice, if
any, required by the Lease (as modified pursuant to Section 15 hereof) and
subject to the right, if any, of Sublessee to cure any such default within any
applicable grace period provided in the Lease (as modified pursuant to Section
15 hereof), shall have available to it all of the remedies available to Landlord
under the Lease including without limitation Section 14.2 of the Lease (with the
words "Fixed Rent" substituted for "Base Rent" and "Additional Rent" substituted
for "Operating Costs") in the event of a default or failure on the part of the
Sublessor, as tenant thereunder. Such remedies shall be in addition to all other
remedies available to Sublessor at law or in equity.

         11. Brokers.

         Sublessor and Sublessee each represent and warrant to the other that
neither has dealt with any broker or finder in connection with this Sublease
other than Trammell Crow Company (the "Broker") and Sublessor and Sublessee each
agree to indemnify, defend and hold the other harmless from and against any and
all liabilities, losses, obligations, damages, penalties, claims, costs and
expenses (including, without limitation, attorneys' fees and other charges)
arising out of (i) any breach of the foregoing representation and/or (ii) any
claim, demand or proceeding for a real estate brokerage commission, finder's fee
or other compensation made by any person or entity other than the Brokers in
connection with this Sublease claiming to have dealt with the indemnifying party
and not such other party. If, as and when this Sublease is executed, and the
first month's Fixed Rent is paid, Sublessor shall pay the Broker 50% of the fee
and commission due them pursuant to a separate agreement, with the remaining 50%
to be paid by Sublessor upon occupancy of, and the commencement of payments of
Fixed Rent by Sublessee for, the Subleased Premises.

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         12. Indemnification of Sublessor.

         (1) Sublessee agrees to indemnify, defend and hold Sublessor harmless
from, any and all liabilities, losses, obligations, damages, penalties, claims,
costs and expenses (including, without limitation, attorneys' fees and other
charges) which are paid, suffered or incurred by Sublessor as a result (i) any
personal injuries or property damage occurring in, on or about the Subleased
Premises during the Term caused by Sublessee or Sublessee's agents, contractors,
servants, employees, invitees or licensees, (ii) any work or thing done, or any
condition created, by Sublessee or Sublessee's agents, contractors, servants,
employees, invitees or licensees in, on or about the Subleased Premises or the
Building during the Term, or (iii) any act or omission of Sublessee or
Sublessee's agents, contractors, servants, employees, invitees or licensees
during the Term except to the extent caused wholly by the negligence,
recklessness or intentional misconduct of Sublessor.

         (2) Sublessor agrees to indemnify, defend and hold Sublessee harmless
from, any and all liabilities, losses, obligations, damages, penalties, claims,
costs and expenses (including, without limitation, attorneys' fees and other
charges) which are paid, suffered or incurred by Sublessee as a result any
personal injuries or property damage occurring in, on or about the Subleased
Premises in connection with Sublessor's use of the telephone closets, as
described in Section 1(c) of this Sublease, during the Term or otherwise caused
by the acts or negligence of Sublessor or Sublessor's agents, contractors,
servants, employees, invitees or licensees during the Term, except to the extent
caused wholly by the negligence, recklessness or intentional misconduct of
Sublessee. La no event shall Sublessor be liable for any indirect, incidental,
special, punitive or consequential damages, including lost profit or revenues,
even if informed of their possibility.

         13. Termination of Lease.

         If the term of the Lease is terminated prior to the Expiration Date,
then, subject to Section 7(b) hereof, this Sublease shall immediately terminate
and Sublessor shall not be liable to Sublessee by reason thereof.

         14. Approvals or Consents.

         In all provisions of the Lease requiring the approval or consent of
Landlord, Sublessee shall be required to obtain the express written approval or
consent of Sublessor.

         15. Time Limits.

         The parties agree that unless otherwise expressly modified herein, the
time limits set forth in the Lease for the giving of notices, making demands,
payment of any sum, the performance of

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any act, condition or covenant, or the exercise of any right, remedy or option,
are modified for the purpose of this Sublease by (i) shortening the same in each
instance by three (3) business days if requiring performance by Sublessee, and
(ii) by lengthening the same in each instance by three (3) business days if
requiring performance by Sublessor, so that notices may be given, demands made,
any act, condition or covenant performed and any right or remedy hereunder
exercised, by Sublessor or Sublessee, as the case may be, within the time limits
relating thereto contained in the Lease. Sublessor and Sublessee shall, promptly
after receipt thereof, furnish to each other a copy of each notice, demand or
other communication received from Landlord with respect to the Subleased
Premises.

         16. Assignment and Subletting.

         (1) Sublessee shall not assign, sublet, mortgage, pledge or encumber
this Sublease, the Subleased Premises, or any interest in the whole or in any
portion thereof, without the prior written consent of Sublessor (which consent
shall not be unreasonably withheld or delayed). For purposes of this Article 16,
a transfer, in one transaction or a series of transactions, of a controlling
interest in the capital stock or other ownership or membership interests in
Sublessee shall be deemed to be an assignment of this Sublease. If Sublessee
makes any such assignment, mortgage, sublease or pledge (whether with or without
Sublessor's written consent), Sublessee named herein shall nonetheless remain
primarily liable for the performance and observation of all of the terms of this
Sublease required to be observed or performed by Sublessee hereunder. Fifty
percent (50%) of the amount by which any rentals, fees and charges from time to
time received by Sublessee in connection with any such assignment or sublease
(after first netting out any reasonable brokerage and re-letting expenses
actually incurred by Sublessee), exceed the Fixed Rent and Additional Rent
payable to Sublessor hereunder (hereinafter referred to as "Excess Rental")
shall be paid immediately by Sublessee to Sublessor as Additional Rent under
this Sublease. In such event, the Fixed Rent and Additional Rent payable by
Sublessee to Sublessor under this Sublease for the balance of the Sublease Term
shall be increased by an amount equal to the Excess Rental. In addition,
Sublessor shall have the option, in its sole discretion, to terminate this
Sublease effective as of the proposed effective date of any assignment or
sublease, by giving Sublessee written notice thereof within ten (10) days after
Sublessor's receipt of said notice from Sublessee; and in the event Sublessee
shall propose to sublet only a portion of the Subleased Premises, Sublessor
shall have the additional option to terminate this Sublease as to that portion
of the Subleased Premises, Sublessor shall have the additional option to
terminate this Sublease as to that portion of the Subleased Premises proposed to
be sublet. Should Sublessor not elect to so terminate this Sublease in
connection with any proposed subletting or assignment, Sublessor shall continue
to have the right to disapprove same (subject to the terms herein). Upon any
subletting or assignment by Sublessee in accordance with the terms hereof, any
extension option granted herein shall become null and void. Consent by Sublessor
to one or more assignments or sublettings shall not operate as a waiver of
Sublessor's rights as to any subsequent assignments or sublettings.

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         (2) If Sublessee should desire to assign this Sublease or sublet the
Subleased Premises (or any part thereof), Sublessee shall give Sublessor written
notice thirty (30) days in advance of the proposed effective date of any
proposed assignment or sublease, specifying (i) the name, current address, and
business of the proposed assignee or sublessee, (ii) the amount and location of
the space within the Subleased Premises proposed to be so subleased, (iii) the
proposed effective date and duration of the assignment or subletting, and (iv)
the proposed rent or consideration to be paid to Sublessee by such assignee or
sublessee. Sublessee shall promptly supply Sublessor with financial statements
and other information as Sublessor may reasonably request to evaluate the
proposed assignment or sublease. Sublessee agrees to reimburse Sublessor for
Sublessor's reasonable attorney's fees incurred.

         (3) Notwithstanding anything to the contrary in this Sublease,
Sublessee shall have the right, for which Sublessor's prior written consent
shall not be withheld or delayed, at any time, and from time to time to transfer
to any entity into or with which Sublessee is merged or consolidated, or to
which substantially all of Sublessee's assets are transferred, or to any
corporation that controls or is controlled by Sublessee, or is under common
control with Sublessee, provided in any of such events (a) the successor to
Sublessee has a net worth (computed in accordance with generally accepted
accounting principles) of at least $100,000,000, and (b) proof satisfactory to
Sublessor of such net worth shall have been delivered to Sublessor within five
(5) days after the effective date of any such transaction. This covenant and
assignment shall run with the land and shall bind Sublessee and Sublessee's
heirs, executors, administrators, personal, representatives, successors and
assigns.

         (4) If Sublessee assigns, sublets or makes any other transfer of all or
any portion of its interest(s) hereunder, Sublessee named in this Sublease shall
remain directly and primarily responsible for the faithful performance and
observance of all of the covenants and obligations on Sublessee's part to be
performed in this Sublease.

         (5) Any assignee or subtenant hereunder shall be bound by and shall
comply with all of the terms and provisions in this Sublease. As a condition to
the effectiveness of any assignment that is permitted hereunder, the assignee
shall, by an instrument in writing, within five (5) days after the effective
date of the applicable transaction assume and agree to perform (for the express
benefit of Sublessor) the terms hereof; and as a condition to the effectiveness
of any sublease that is permitted hereunder, the subtenant shall acknowledge in
writing (for the express benefit of Sublessor) within five (5) days after the
effective date of the applicable transaction the existence of this Sublease and
shall covenant not to do or permit to be done anything that would constitute a
breach thereof.

         (6) Notwithstanding anything contained in this Paragraph 16 to the
contrary, provided Sublessee is not in default hereunder, Sublessor shall not
unreasonably withhold or delay its consent to Sublessee's request to assign this
Sublease or to sublease the Subleased Premises. In

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determining the reasonableness of Sublessor's approval of or failure to consent
to Sublessee's assignment of this Sublease or the subleasing of the Subleased
Premises, Sublessor may take into consideration all relevant factors surrounding
the proposed sublease and assignment, including without limitation, the
following:

                  (1)      the business reputation of the proposed assignee or
                           subtenant and its partners, officers, directors and
                           stockholders;

                  (2)      the nature of the business and the proposed use of
                           the Subleased Premises by the proposed assignee or
                           subtenant;

                  (3)      the financial condition of the proposed assignee or
                           subtenant;

                  (4)      the effect that the proposed assignee or subtenant
                           would have on the operations and maintenance of the
                           Building;

                  (5)      whether or not the proposed assignee or subtenant is
                           presently a competitor (or subsidiary, affiliate or
                           parent of a competitor);

                  (6)      restrictions, if any, contained in other leases, or
                           agreements affecting the Building;

                  (7)      the extent to which the proposed subtenant or
                           assignee and Sublessee provide Sublessor with
                           assurances reasonably satisfactory to Sublessor as to
                           the satisfaction of Sublessee's obligations
                           hereunder, including the payment of rent;

                  (8)      restrictions, if any, imposed by the holder of any
                           mortgage encumbering the Building or any portion
                           thereof;

taking into account the fact that the Building is Sublessor's corporate
headquarters and that portions of the Subleased Premises are visible from
Building common areas, including the atrium, and from other premises occupied by
Sublessor and by other tenants.

         17. End of Term.

         Sublessee acknowledges that possession of the Subleased Premises must
be surrendered to Sublessor on the Expiration Date or earlier termination of
this Sublease (subject to the force majeure) in the same condition as set forth
in Section 5(b) hereof, subject to normal wear and tear or casualty. Sublessee
agrees to indemnify, defend and hold Sublessor harmless from, any and all
liabilities, losses, obligations, damages, penalties, claims, costs and expenses
(including,

                                      -11-
<PAGE>   12
without limitation, attorney's fees and other charges) which are paid, suffered
or incurred by Sublessor as a result of the failure of, or the delay by,
Sublessee in so surrendering the Subleased Premises, including, without
limitation, any claims made by Sublessor or any succeeding tenant founded on
such failure or delay.

         18. Destruction, Fire and other Casualty.

             [Intentionally Omitted]

         19. Eminent Domain.

         With respect to Section 11.2 of the Lease, in the event Sublessor
receives an award for relocation benefits and moving expenses Sublessee shall be
entitled to a share provided that (i) Sublessee advanced Sublessor its
proportionate share of the expenses incurred by Sublessor in connection with any
effort to obtain such an award and (ii) the condemnation or taking adversely
affects Sublessee.

         20. Notices.

         Any notice, request or demand ("Notice") permitted or required to be
given by the terms and provisions of this Sublease, or by any law or
governmental regulation, either by Sublessor or Sublessee, shall be in writing.
Unless otherwise required by law or regulation, all Notices shall be given and
shall be deemed to have been served and given by either of the parties hereto
and received by the other party, on the date when the party giving the Notice
shall have mailed the Notice by any nationally recognized overnight delivery
service (with signature required) or hand delivered the Notice (with signature
required), addressed to the other party at the address of the other party first
set forth above. A copy of all Notices sent (i) to Sublessor shall be sent to
the address set forth on the first page of this Sublease, Attention: General
Counsel and (ii) to Sublessee shall be sent to Michael S. Palin, Chief Financial
Officer at the address set forth in the preface of this Sublease, except that
prior to the Commencement Date, the address shall be 60 Hickory Drive, Waltham,
Massachusetts 02451. Either party hereto may designate a different address for
Notices to such party by serving Notice of such change in accordance with this
Section 19.

         21. Extension.

         Sublessor may, at its sole election, give notice to Sublessee at least
twelve (12) months prior to the Expiration Date, of Sublessor's good faith
determination that all or a substantial portion of the Subleased Premises is or
will be needed by Sublessor within the two (2) years following the Expiration
Date for actual occupancy by Sublessor or one or more of its affiliates. Unless
Sublessor shall give timely such notice, Sublessee shall have the option, by
notice to Sublessor at least nine (9) months prior to the Expiration Date, to
extend the Term of this

                                      -12-
<PAGE>   13
Sublease for one (1) period of two (2) years. If Sublessee fails to give timely
such notice of extension, Sublessee's extension option shall be conclusively
deemed waived and of no further force or effect time being of the essence, Said
extension option is further subject to the conditions that Sublessee shall not
then (x) have assigned this Sublease or sublet more than twenty-five (25%)
percent of the Subleased Premises or (y) be in default under this Sublease
beyond such grace or cure period, if any, as may be applicable to such default.
The rate of Fixed Rent payable by Sublessee during such two-year extension
period shall be the higher of (i) the Fixed Rent and Additional Rent payable
during the then current lease year immediately proceeding such two-year
extension period or (ii) Fixed Rent determined pursuant to the method for
determining "Base Rent" set forth in subsection (c) (but not subsection (d)) of
Section 2.3 of the Lease, except that "Extension Market Rate" shall mean the
fair market rental rate for the Subleased Premises in its then "as is" condition
for such two-year extension term, upon and otherwise upon and subject to the
other terms and provisions of this Sublease, with "Sublessor" substituted for
"Landlord" and "Sublessee" substituted for "Sublessee".

         22. Security Deposit.

         Sublessee shall deposit with Sublessor, as security for the faithful
performance and observance by Sublessee of the terms, conditions, covenants and
provisions of this Sublease, including the timely and proper surrender of
possession of the Subleased Premises the following security:

         (1) Sublessee shall deliver to Sublessor upon execution of this
Sublease a clean, irrevocable, non-documentary (other than the sight draft
referred to therein) and unconditional Letter of Credit (the "Letter of Credit")
in an amount equal to Four Hundred Thirty-Three Thousand Six Hundred Forty and
75/100 Dollars ($433,640.75) (the "Security Deposit" issued by and drawn upon
any commercial bank (hereinafter referred to as the "Issuing Bank") with offices
for banking purposes in the City of Boston or the greater Boston area and which
shall mean Silicon Valley Bank or any other bank, trust company, national
banking association or savings and loan association which (or the parent company
of which) have outstanding unsecured, uninsured and unguaranteed indebtedness
that is then rated, without regard to qualification of such rating by symbols as
"+" or "-" or numerical notation, "Aa" or better by Moody's Investors Service
and "AA" or better by Standard & Poor's Corporation, and has combined capital,
surplus and undivided profits of not less than $500,000,000.00, which Letter of
Credit shall have a term of not less than one year, be in form and content
satisfactory to Sublessor, be for the account of Sublessor and be fully
transferable by Sublessor without the payment of any fees or charges, it being
agreed that if any such fees or charges shall be so imposed, then such fees or
charges shall be paid by Sublessee. The Letter of Credit shall provide that it
shall be deemed automatically renewed, without amendment, for consecutive
periods of one year each thereafter during the term of this Sublease, unless the
Issuing Bank sends notice (the "Non-Renewal Notice") to Sublessor by certified
mail, return receipt requested, not less than

                                      -13-
<PAGE>   14
thirty (30) days next preceding the then expiration date of the Letter of Credit
that it elects not to have such Letter of Credit renewed. Additionally, the
Letter of Credit shall provide that Sublessor shall have the right, exercisable
within twenty (20) days of its receipt of the Non-Renewal Notice, by sight draft
on the Issuing Bank to receive the monies represented by the existing Letter of
Credit and to hold such proceeds pursuant to the terms of this Paragraph 21 as a
cash security pending the replacement of such Letter of Credit. In the event
that Sublessee defaults in respect of any of the terms, provisions, covenants or
conditions of this Sublease, including, but not limited to, the payment of Fixed
Rent and Additional Rent, applicable after any notice and beyond the expiration
of any applicable grace period, Sublessor may notify the Issuing Bank and
thereupon receive all the monies represented by the Letter of Credit and use,
apply or retain the whole or any part of such proceeds, to the extent required
for the payment of any Fixed Rent or Additional Rent or any other sum as to
which Sublessee is in default or for any sum which Sublessor may expend or may
be required to expend by reason of Sublessee's default in respect of any of the
terms, provisions, covenants or conditions of this Sublease, including, but not
limited to, any damages or deficiency in the reletting of the Subleased
Premises, whether such damages or deficiency accrue or accrues before or after
summary proceedings or other reentry by Sublessor. If Sublessor applies or
retains any part of the proceeds of the Letter of Credit, Sublessee, upon
demand, shall deposit with Sublessor the amount so applied or retained so that
Sublessor shall have the full deposit on hand at all times during the Term. If
Sublessee shall surrender the Subleased Premises to Sublessor in accordance with
this Sublease and shall pay all Fixed Rent and Additional Rent due hereunder in
full through and including the Expiration Date of this Sublease and no other
default shall have occurred and be continuing, the Letter of Credit shall be
returned to Sublessee within twenty (20) days after the Expiration Date and
delivery of the entire possession of the Subleased Premises to Sublessor.
Sublessee expressly agrees that Sublessee shall have no right to apply any
portion of the Security Deposit against any Sublessee's obligations to pay Fixed
Rent or Additional Rent hereunder and, if Sublessee shall seek to so apply such
Security Deposit, Sublessee shall pay liquidated damages to Sublessor in a sum
equal to two (2) times the amount of any such unpaid Fixed Rent or Additional
Rent. In the event of a transfer or assignment of the Sublease, within thirty
(30) days of notice of such transaction, Sublessor at its sole cost and expense,
shall arrange (i) for the transfer of the Letter of Credit to the new
sublandlord as designated by Sublessor in such notice or (ii) to have the Letter
of Credit reissued in the name of the new sublandlord; and Sublessor shall
thereupon be released by Sublessee from all liability for the return of such
security. Sublessee shall look solely to the new sublandlord for the return of
such Letter of Credit and the provisions hereof shall apply to every transfer or
assignment made of the security to a new sublandlord. Sublessee further
covenants and agrees that it shall not assign or encumber or attempt to assign
or encumber the Letter of Credit deposited herein as security and that neither
Sublessor nor its successors or assigns shall be bound by any such assignment,
encumbrance, attempted assignment or attempted encumbrance.

         (2) Notwithstanding anything to the contrary contained in this
Sublease, provided that no default, beyond any applicable notice and grace
period, shall have occurred and be continuing

                                      -14-
<PAGE>   15
as of any Reduction Date, then the Security Deposit shall be reduced over the
Term as follows: (i) upon the first (1st) anniversary of the Commencement Date,
the Security Deposit shall be reduced to an amount equal to Two Hundred
Eight-Nine Thousand Ninety-Three and 83/100 Dollars ($289,093.83); (ii) upon the
second (2nd) anniversary of the Commencement Date, the Security Deposit shall be
reduced, and shall remain for the balance of the Term at, to an amount equal to
One Hundred Forty-Four Thousand Five Hundred Forty-Six and 92/100 Dollars
($144,546.92) (each of the anniversary dates provided for in (i) and (ii) above
is individually a "Reduction Date" and collectively, the "Reduction Dates"). In
connection with such reduction, provided that Sublessee shall tender to
Sublessor a replacement or amended Letter of Credit in the appropriately reduced
amount of the Security Deposit, Sublessor shall promptly exchange the Letter of
Credit then held by Sublessor for the Letter of Credit tendered by Sublessee in
the reduced amount set forth above. In the alternative, and provided that no
default, beyond any applicable notice and grace period, shall have occurred and
be continuing as of any Reduction Date, Sublessor shall, within ten (10)
business days following request from Sublessee furnish to the Issuing Bank a
letter signed by Sublessor acknowledging that no default by Sublessee has
occurred and is continuing beyond applicable notice and grace, and agreeing to
such reduction of the Security Deposit as provided above.

         23. Other Sublessee Rights.

         Sublessee shall have the right to use, on a non-reserved basis, a
maximum of 85 of the parking spaces made available to Sublessor pursuant to
Section 4.4 of the Lease on Levels 3, 4 and 5 of the Parking Facility. Sublessor
reserves the right to regulate and control such parking usage by Sublessee its
employees, licensees and invitees with parking stickers, tags, cards or any
other reasonable procedure. Sublessee shall participate and cooperate in such
control procedure and agrees that in the event of excess parking by Sublessee,
its employees, licensees or invitees, any of the offending vehicles or other
Sublessee vehicles may be denied parking privileges and/or towed at Sublessee's
expense and Sublessee may be subjected to a fine or penalty of $250.00 per
vehicle, which tow charges and fines or penalties shall be payable as Additional
Rent on each occasion. Sublessor shall attempt in good faith, but shall have no
obligation, to contact Sublessee prior to towing any offending vehicle. If
during any twelve month period Sublessor shall give written notice of such
excess parking on three or more occasions, any further such excess parking
during such twelve month period shall, at Sublessor's election, be deemed to
constitute a material incurable default under this Sublease. Sublessee shall
have the right to Building standard signage in the interior lobby of the
Subleased Premises and to representative inclusion in the Building lobby
directory, except that the provisions of Article 19, other than subsections (b),
(j) and (l) shall be applicable to Sublessee's lobby signage as if such signage
were "Tenant Building Signage", Sublessor were "Landlord" and Sublessee were
"Tenant" thereunder. Sublessor agrees to provide Building standard directional
signage to the Subleased Premises in the second floor and P-2 ground level
elevator lobbies and that its consent shall not be unreasonably withheld for
tenant signage at the entrance to the Subleased Premises.

                                      -15-
<PAGE>   16
Employees of Sublessee shall have the right to use the cafeteria, as well as the
fitness center in the Building from time to time maintained by Sublessor,
subject to such rules and regulations and, in the case of the fitness center the
payment of such per-employee annual fee, as Sublessor may reasonably establish
from time to time.

         24. Electricity Charge.

         Sublessee shall pay monthly, as Additional Rent, as and when payments
of Fixed Rent are due, an electricity charge equal to the sum of Two Thousand
One Hundred Fifty-Seven and 42/100 Dollars ($2,157.42) in respect of Sublessor's
costs of providing electricity to the Subleased Premises. Sublessee's use of
electricity within or serving its uses of the Subleased Premises shall not
exceed that reasonably required for normal office use. If Sublessor at any time
reasonably determines that Sublessee's use of electricity exceeds reasonable
requirements for normal office use, and Sublessor elects to permit such excess
usage, Sublessor may, at Sublessee's expense, submeter such space and the
electricity charge payable monthly by Sublessee shall be increased to such
amount as Sublessor from time to time reasonably estimates based upon such
submetering and specifies by notice to Sublessee, with periodic adjustments, not
less frequently than annually, as Sublessee's actual usages are known. In no
event shall Sublessee be obligated to pay more than the actual cost of such
electricity as reasonably determined by Sublessor.

         25. Sublessee's Insurance.

         (1) Sublessee shall obtain and keep in full force and effect during the
term of this Sublease:

                  (1)      a policy of commercial general public liability
                           insurance, on a primary and non-contributory basis,
                           including bodily injury and property damage, with a
                           broad form contractual liability endorsement or the
                           then equivalent of such coverage, protecting
                           Sublessee, Sublessor, Sublessor's employees and
                           agents and any other parties designated by Sublessor
                           having an interest in the Subleased Premises, as
                           additional insureds, on an occurrence basis against
                           claims for personal injury, death and/or property
                           damage occurring in or about the Subleased Premises,
                           and under which the insurer agrees to indemnify,
                           defend and hold Sublessee harmless from and against,
                           among other things, all cost, expense and/or
                           liability arising our of or based upon any and all
                           claims, accidents, injuries and damages for which
                           Sublessee shall be liable in accordance with this
                           Sublease and the Lease, with any umbrella and primary
                           commercial general liability policy on a coterminous
                           basis. The minimum limits for liability shall be a
                           combined single limit with respect to each occurrence
                           in an amount of not less than

                                      -16-
<PAGE>   17
                           $5,000,000 for injury (or death) and damage to
                           property (or in any increased amount reasonably
                           required by Sublessor); and

                  (2)      insurance against loss or damage by fire, and such
                           other risks and hazards (including burglary, theft,
                           vandalism, sprinkler leakage damage, breakage of
                           glass within the Subleased Premises as are insurable
                           under then available standard forms of "all risk"
                           insurance policies, to Sublessee's personal property
                           and Sublessee's alterations for the full replacement
                           cost value thereof (including an "agreed amount"
                           endorsement having a deductible amount, if any, as
                           shall be determined by Sublessee in the exercise of
                           Sublessee's commercially reasonable discretion);

                  (3)      during the performance of any alteration, until
                           completion hereof, builder's risk insurance, with no
                           restrictions on coverage on an "all risk" basis and
                           on a completed value form for full replacement value
                           covering the interests of Sublessor and Sublessee,
                           with Sublessor as a named insured; and

                  (4)      worker's compensation insurance as required by law,
                           with express wavier of subrogation for the benefit of
                           Sublessor.

         (2) Prior to the time such insurance is first required to be carried by
Sublessee and thereafter, at least thirty (30) days prior to the expiration of
any such policies, Sublessee agrees to deliver to Sublessor evidence of payment
for the policies together with certificates evidencing such insurance. All such
certificates shall contain endorsements that (a) such insurance may not be
modified or canceled or allowed to lapse except upon thirty (30) days' written
notice to Sublessor by certified mail, return receipt requested, containing the
policy number and the names of the insured and the certificate holder, and (b)
Sublessee shall be solely responsible for payment of all premiums under such
policies and Sublessor shall have no obligation for the payment thereof
notwithstanding that Sublessor is or may be named as an insured. Sublessee's
failure to provide and keep in force the aforementioned insurance shall be
regarded as a material default hereunder, entitling Sublessor to exercise any or
all of the remedies as provided in this Sublease in the event of Sublessee's
default. All insurance required to be carried by Sublessee pursuant to the terms
of this Sublease shall be effected under valid and enforceable policies issued
by reputable and independent insurers permitted to do business in The
Commonwealth of Massachusetts and rated in Best's Insurance Guide, or any
successor thereto (of if there be none, an organization having a national
reputation) as having a general policy-holder rating of "A" and a financial
rating of at least "XIII". Sublessee shall not carry separate or additional
insurance, concurrent in form or contributing, in the event of any loss or
damage, with any insurance required to be obtained by Sublessee under this
Sublease.

                                      -17-
<PAGE>   18
         (3) Sublessee shall procure an appropriate clause in, or endorsement
on, any such "all risk" or fire or extended coverage insurance covering the
Subleased Premises, the personal property, fixtures or equipment located thereon
or therein, pursuant to which the insurance company waives subrogation or
consents to a wavier of right of recovery by the insured prior to any loss. It
is expressly understood and agreed that Sublessor will not be obligated to carry
insurance on Sublessee's property or Sublessee's work or insurance against
interruption of Sublessee's business.

         (4) Sublessee hereby releases Sublessor (its servants, agents,
employees and invitees) with respect to any claim (including a claim for
negligence) which Sublessee might otherwise have against Sublessor for loss,
damage or destruction with respect to its property by fire or casualty
(including rental value or business interruption, as the case may be) occurring
during the term of this Sublease.

         26. Governing Law.

         The provisions of this Sublease shall be governed and interpreted in
accordance with the laws of The Commonwealth of Massachusetts.

         27. Miscellaneous.

         (1) This Sublease may not be modified, amended, extended, renewed,
terminated or otherwise modified by either Sublessor or Sublessee except by a
written instrument signed by both of the parties hereto.

         (2) It is acknowledged and agreed that all understandings and
agreements heretofore had between the parties hereto are merged in this
Sublease, which alone fully and completely expresses their agreement with
respect to the subject matter hereof. This Sublease has been executed and
delivered after full investigation by each of the parties hereto, and neither
party hereto has relied upon any statement, representation or warranty which is
not specifically set forth in this Sublease.

         (3) This Sublease does not constitute an offer to sublease the
Subleased Premises to Sublessee and Sublessee shall have not rights with respect
to the leasing of the Subleased Premises unless and until Sublessor, in its sole
and absolute discretion, elects to be bound hereby executing and unconditionally
delivering to Sublessee an original counterpart hereof.

         (4) With respect to Section 16.3 of the Lease, Sublessor agrees to
provide Sublessee with copies of any environmental reports or assessments
concerning the Subleased Premises that are provided to Sublessor by Landlord.

                                      -18-
<PAGE>   19
         IN WITNESS WHEREOF, this Sublease has been duly executed as of the day
and year first above written.

                          SUBLESSOR:

                          RENAISSANCE WORLDWIDE, INC.


                          By:  /s/ Ronan O'Brien
                               ---------------------------------
                               Name:  Ronan O'Brien
                               Title:  Corporate Counsel


                          SUBLESSEE:

                          SITARA NETWORKS, INC.


                          By:  /s/ Michael S. Palin
                               ---------------------------------
                               Name:  Michael S. Palin
                               Title:  Chief Financial Officer


                                      -19-