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                                                                  EXHIBIT 10.11

                         STANDARD FORM SUBLEASE (LEGACY)

                               SUBLEASE AGREEMENT

                   BASIC SUBLEASE INFORMATION (DEFINED TERMS)

Effective Date:        April 27, 2000

Master Lease Date:     August 2, 1993, as amended by that certain First
Amendment to Lease Agreement dated as of February 14, 1994, that certain Second
Amendment to Lease dated as of December 22, 1995, that certain Third Amendment
to Lease dated as of December 27, 1996, that certain Fourth Amendment to Lease
dated as of December __, 1997, and that certain Fifth Amendment to Lease dated
as of March 16, 2000.

Landlord:               WHLW Real Estate Limited Partnership, a Delaware real
                        estate limited partnership

Tenant:                 Autodesk, Inc., a Delaware corporation

Tenant's Address:       Autodesk, Inc.
                        111 McInnis Parkway
                        San Rafael, California 94903
                        Attention: Corporate Real Estate and Facility

   with a copy to:      Shartis Friese & Ginsburg, LLP
                        One Maritime Plaza, 18th Floor
                        San Francisco, California 94111
                        Attention: Alan J. Robin

Premises:               Improved real property as more particularly described
                        in the Master Lease, attached hereto as Exhibit B,
                        consisting of approximately 127,102 rentable square
                        feet.

Permitted Uses:         Uses permitted under the Master Lease.

Subtenant:              ObjectSwitch, Inc., a California corporation, dba
                        Kabira Technologies, Inc.

Subtenant's Address:    ObjectSwitch Corporation
                        1 McInnis Parkway
                        San Rafael, California 94903
                        Attention Greg Straughn

Sublease Premises:      That portion of the Premises, as more particularly
                        described in the Sublease Premises Floor Plan, attached
                        hereto as Exhibit A, consisting of 5,087 rentable
                        square feet.


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Sublease Premises
Address:                4000 Civic Center Drive, Suite(s) 200, San  Rafael,
                        California

Building:               4000 Civic Center Drive, San Rafael, California

Sublease Term:          Approximately eight (8) months unless extended per
                        Section 2b.

Sublease
Commencement Date:      The Date Tenant delivers possession of the Sublease
                        Premises to Subtenant after approval of this Sublease
                        by Landlord but not earlier than May 1, 2000.

Expiration Date:        December 21, 2000 unless sooner terminated or extended
                        as provided in the Master Lease and this Sublease.

Rent Commencement
Date:                   The Commencement Date

Base Rent:              Twelve Thousand Nine Hundred Seventy-one and 85/100
                        Dollars ($12,791.85) per month from the Sublease
                        Commencement Date through the First Extension term but
                        not exceeding the first twelve (12) consecutive months
                        of the Lease Term.

Base Rent Adjustment:   On the first day of the thirteenth (13th) month
                        following the Commencement Date, Base Rent shall be
                        increased to Thirteen Thousand Four Hundred Ninety and
                        72/100 Dollars ($13,490.72).

Subtenant's
Security Deposit:       Twelve Thousand Nine Hundred Seventy-two Dollars
                        ($12,972.00)

Parking Area:           Four Hundred Sixteen (416) non-exclusive and
                        non-designated spaces.

Broker:
Tenant's Broker:        Colliers International
Subtenant's Broker:     Cushman & Wakefield, Inc.

Exhibits:               Exhibit A - Sublease Premises Floor Plan
                        Exhibit B - Master Lease
                        Exhibit C -  Parking Area


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         THIS SUBLEASE AGREEMENT ("Sublease") is entered as of the Effective
Date by and between Tenant and Subtenant.

         THE PARTIES ENTER this Sublease on the basis of the following facts,
understandings and intentions:

         A.       Tenant is presently a tenant of the Premises in the Building
pursuant to the Master Lease by and between Landlord and Tenant. A copy of the
Master Lease with all exhibits and addenda thereto, is attached hereto as
Exhibit B.

         B.       Tenant desires to sublease the Sublease Premises to Subtenant
and Subtenant desires to sublease the Sublease Premises from Tenant on all of
the terms, covenants and conditions herein after set forth.

         C.       All of the terms and definitions in the Defined Terms section
are incorporated herein by this reference.

         NOW, THEREFORE, IN CONSIDERATION of the mutual covenants and promises
of the parties, the parties hereto agree as follows:

     1.  Sublease.

         (a) Tenant hereby subleases to Subtenant, and Subtenant hereby
subleases from Tenant the Sublease Premises for the Sublease Term upon all of
the terms, covenants and conditions herein contained. In addition, Tenant shall
lease to Subtenant, and Subtenant shall lease from Tenant, any and all permanent
improvements ("Improvements") on the Sublease Premises constructed and/or owned
by Tenant, upon all of the terms, covenants and conditions herein contained. As
used herein, "Sublease Premises" shall include the Sublease Premises and the
Improvements.

         (b) In the event any space currently leased by Tenant adjacent to the
Sublease Premises currently occupied by ICPlanet becomes available to sub-lease
to a third party ("Available Space"), Tenant agrees to provide Subtenant with a
right of first offer to lease the Available Space on the terms and conditions
which Tenant proposes to offer the Available Space to the sublease market (the
"Offer Terms"). Subtenant shall have five (5) business days in which to notify
Tenant that it has elected to accept the Offer Terms. If Subtenant accepts the
Offer Terms, Tenant and Subtenant shall enter into a sublease with respect to
the Available Space. If Subtenant does not accept the Offer Terms, Tenant shall
be able to lease the Available Space to any third party on such terms and
conditions as it may agree to. Subtenant understands and agrees that the rent
for the Available Space and the term for which the Available Space may be
subleased may not be the same as the rent and term of this Sublease.
Notwithstanding anything set forth herein, Subtenant's right to sublease the
Available Space is subject to the approval of the Landlord pursuant to the terms
and conditions of the Master Lease.

     2.  Sublease Term.

         (a) Initial Term. The Term of this Sublease shall commence on the
Commencement Date and shall end, unless sooner terminated or extended as
provided in the Master Lease and this Sublease, on the Expiration Date.


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         (b) First Extension. In the event and only in the event that Tenant
extends the term of the Master Lease, Tenant shall notify Subtenant of such
extension ("Extension Notice") and the term of this Sublease shall automatically
be extended to November 30, 2001, upon the terms and conditions set forth in
this Sublease. Subtenant shall pay the rent as described in the Base Rent
Adjustment paragraph in the Basic Sublease Information Section of this Sublease.

         (c) Second Extension. In the event and only in the event that Tenant
extends the term of the Master Lease, Subtenant shall have shall the right to
extend the Term of this Sublease from November 30, 2001, to November 30, 2002
(the "Extension Term"). Subtenant shall provide a notice of extension to Tenant
not earlier than May 1, 2001, and not later than May 31, 2001, of its election
to extend the Term to November 30, 2002 ("Subtenant Extension Notice"). If
Subtenant does not send a Subtenant Extension Notice, Subtenant will be deemed
to have elected not to extend the Term. Subtenant shall not have the right to
extend the Term if an Event of Default has occurred with respect to Subtenant or
if the Sublease has been assigned by Subtenant or if Subtenant has subleased
more than 50% of the Sublease Premises. In addition, Subtenant shall not have
the right to extend the Term, if within thirty (30) days after receipt of the
Subtenant Extension Notice, Tenant notifies Subtenant that it intends to
recapture the Sublease Premises on the Expiration Date for its own use and
occupancy.

         (d) Consent for Extension. In the event Subtenant and Tenant seek to
extend the term of the Sublease beyond November 30, 2001, such extension shall
be subject to the consent of Landlord. Upon approval by Landlord, Tenant and
Subtenant shall enter into an amendment to this Sublease which shall be in
accordance with the terms and conditions of the Master Lease as extended. The
amendment to the Sublease shall be subject to the approval of Landlord.

         (e) Base Rent During Extension. The Base Rent during the Extension Term
shall be the fair market value of the Sublease Premises in its as is condition
for a term of one year as reasonably determined by Tenant ("FMV Determination").
If Subtenant disagrees with the FMV Determination, Subtenant shall have ten (10)
business days after its receipt of the FMV Determination to rescind the
Subtenant Extension Notice.

     3.  Condition of Sublease Premises.

         (a) As-Is Condition. Subtenant acknowledges that Subtenant has
conducted Subtenant's own investigation of the Sublease Premises, the physical
condition thereof, including compliance of the Sublease Premises with all laws
and regulations, accessibility and location of utilities, improvements,
existence of hazardous materials, including but not limited to asbestos,
asbestos containing materials, polychlorinated biphenyls (PCB) and earthquake
preparedness, and such other matters which in Subtenant's judgment affect or
influence Subtenant's use and suitability of the Sublease Premises. Subtenant
recognizes that Tenant would not sublease the Sublease Premises except on an "as
is" basis and acknowledges that Tenant has made no representations of any kind
in connection with improvements or physical conditions on, or bearing on, the
use of the Sublease Premises. Subtenant shall rely solely on Subtenant's own
inspection and examination of such items and not on any representations of
Tenant, express or implied. Subtenant further recognizes and agrees that neither
Tenant nor Landlord have made any such representations, and neither Landlord nor
Tenant shall be required


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to perform any work of construction, alteration or maintenance of or to the
Sublease Premises; however, Tenant shall deliver the Sublease Premises to
Subtenant in broom clean condition, reasonable wear and tear and casualty
excepted.

         (b) Subtenant's Work. Subtenant shall demolish interior walls to
combine the three suites and recarpet and re-paint the Sublease Premises (the
"Subtenant Work") based upon mutually agreed upon plans and specifications and a
mutually agreed upon budget which shall be subject to Landlord's approval. All
work shall be performed in accordance with the terms and conditions of the
Master Lease. If Subtenant's work is managed and supervised by Landlord,
Subtenant shall incur a construction management fee of five percent (5%) of the
total construction and architectural costs which shall be payable to Landlord
within ten (10) days of billing by Landlord. Tenant shall reimburse Subtenant
for the actual out of pocket costs of the Subtenant Work within thirty (30) days
after submission of evidence reasonably satisfactory to Tenant of the actual out
of pocket costs incurred by Subtenant for such work. Other than the improvements
described above, Subtenant shall accept, possession of the Sublease Premises in
their "AS-IS" condition as the Sublease Premises exists on the date hereof. In
making and executing this Sublease, Subtenant has relied solely on such
investigations, examinations and inspections as Subtenant has chosen to make or
has made and has not relied on any representation or warranty concerning the
Sublease Premises or the Building, except as expressly set forth in this
Sublease. Subtenant acknowledges that Tenant has afforded Subtenant the
opportunity for full and complete investigations, examinations and inspections
of the Sublease Premises and the common areas of the Building. Subtenant
acknowledges that it is not authorized to make or do any alterations or
improvements in or to the Sublease Premises except as permitted by the
provisions of this Sublease and the Master Lease and subject to the approval
rights of Landlord under the Master Lease. Upon termination of this Sublease,
Subtenant shall shampoo the carpets and deliver the Sublease Premises to Tenant
broom clean and in the same condition as the Sublease Premises were at the
commencement of the Term hereof, reasonable wear and tear excepted. In the event
that Subtenant is allowed to make any improvements or alterations to the
Sublease Premises, including without limitation, additional wiring or cabling
("Alterations"), Subtenant will, at its sole cost and expense, remove all
Alterations from the Sublease Premises and restore the Sublease Premises to the
condition existing as of the Commencement Date, except for any Alterations which
Tenant and Master Landlord agree may remain thereon. In addition, Subtenant will
remove its personal property, furniture and equipment from the Sublease Premises
upon the expiration of the term of this Sublease. If the performance of the
Subtenant Improvements within the Sublease Premises "triggers" a requirement for
code-related upgrades to or improvements of the Master Lease Premises or any
common areas, Tenant and Subtenant agree that Subtenant shall be responsible for
the additional cost of such code-required upgrade or improvements.

     4.  Sublease Subject to Master Lease. Subtenant agrees that all of the
terms, conditions and covenants of this Sublease shall be those stated in the
Master Lease, modified as appropriate so as to make such Articles, and any
Sections contained therein, applicable only to the subleasing hereunder by
Tenant. Whenever the word "Premises" is used in the Master Lease, for purposes
of this Sublease, the word Sublease Premises shall be substituted. Subtenant
shall be subject to, bound by and comply with all of said Articles and Sections
of the Master Lease with respect to the Sublease Premises and shall satisfy all
applicable terms and conditions of the Master Lease for the benefit of both
Tenant and Landlord, it being understood and agreed that

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wherever in the Master Lease the word "Tenant" appears, for the purposes of this
Sublease, the word "Subtenant" shall be substituted, and wherever the word
"Landlord" appears, for the purposes of this Sublease, the word "Tenant" shall
be substituted; and that upon the breach of any of said terms, conditions or
covenants of the Master Lease by Subtenant or upon the failure of Subtenant to
pay Base Rent, Additional Rent or comply with any of the provisions of this
Sublease, Tenant may exercise any and all rights and remedies granted to
Landlord by the Master Lease. In the event of any conflict between this Sublease
and the Master Lease, the terms of the Master Lease shall control.

     5.  Rent.

         (a) Initial Rent. Upon execution hereof, Subtenant shall deliver the
first month's Base Rent to Tenant, to be applied against Subtenant's first
obligation to pay Base Rent hereunder. Subtenant shall pay to Tenant the Base
Rent in advance on the first (1st) day of each month of the Sublease Term,
commencing on the Commencement Date. In the event the last day of the Sublease
Term is not the last day of the calendar month, the Base Rent shall be
appropriately prorated based on a thirty (30) day month. All installments of
Base Rent shall be delivered to Tenant's Address, or at such other place as may
be designated in writing from time to time by Tenant, in lawful money of the
United States and without deduction, abatement or offset for any cause
whatsoever.

         (b) Rent Increase. On the first day of the 13th month following the
Commencement Date, Base Rent shall be increased to $13,490.72 per month.

         (c) Net Rental. Base Rent is inclusive of Operating Expenses and Tax
Expenses during the calendar year 2000, but Subtenant shall pay as Additional
Rent Subtenant's proportionate share of increases in Operating Expenses and Tax
Expenses over Operating Expenses and Tax Expenses for 2000 and for additional
building services, Utility Expenses, Common Area Utility Costs and
Administrative Expenses (all as defined in the Master Lease) or other charges
which are payable by Tenant under the Master Lease as Additional Rent.

         (d) Event of Default. It shall be an event of default ("Event of
Default") under this Sublease if any installment of Base Rent is not paid on the
third (3rd) day of each month during the Term. If an Event of Default occurs
with respect to any payment of Base Rent, Tenant shall have the same rights and
remedies against Subtenant as those of Landlord as set forth in the Master
Lease.

     6.  Security Deposit. Subtenant has deposited the Security Deposit with
Tenant. The Security Deposit shall secure Subtenant's obligations under this
Sublease to pay Base Rent and other monetary amounts, to maintain the Sublease
Premises and repair damages thereto, to surrender the Sublease Premises to
Tenant in clean condition and repair upon termination of this Sublease and to
discharge Subtenant's other obligations hereunder. If Subtenant fails to perform
Subtenant's obligations hereunder, Tenant may, but without any obligation to do
so, apply all or any portion of the Security Deposit towards fulfillment of
Subtenant's unperformed obligations. If Tenant does so apply any portion of the
Security Deposit, Subtenant's failure to remit to Tenant a sufficient amount in
cash to restore the Security Deposit to the original amount within five (5) days
after receipt of Tenant's written demand to do so shall constitute a material
default.

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Upon termination of this Sublease, if Subtenant has then performed all of
Subtenant's obligations hereunder, Tenant shall return the Security Deposit, or
whatever amount remains of the Security Deposit after Tenant applied all or a
portion of the Security Deposit to perform Subtenant's obligations hereunder, to
Subtenant without payment of interest.

     7.  Use. The Sublease Premises shall be used for the Permitted Uses, and
for no other purpose or business without the prior written consent of Tenant. In
no event shall the Sublease Premises be used for a purpose or use prohibited by
the Master Lease.

     8.  Insurance.

         (a) Awards. Notwithstanding anything contained in the Master Lease to
the contrary, for damages suffered by Tenant and not by Landlord, , all
insurance proceeds or condemnation awards received by Tenant from Subtenant's
insurance under the Master Lease shall be deemed to be the property of Tenant.

         (b) Additional Insured. All insurance policies required to be carried
by Subtenant, pursuant to the Master Lease, shall contain a provision whereby
Tenant and Landlord are each named as additional insureds under such policies.
An original certificate of insurance shall be delivered to Tenant and Landlord
by Subtenant as a condition precedent to the effectiveness of this Sublease.

         (c) Waiver of Subrogation. Landlord, by giving Landlord's consent to
this Sublease, and Subtenant hereby mutually waive their respective rights of
recovery against each other for any loss of, or damage to, either parties'
property to the extent that such loss or damage is insured by an insurance
policy required to be in effect at the time of such loss or damage. Each party
shall obtain any special endorsements, if required by its insurer whereby the
insurer waives its rights of subrogation against the other party. This provision
is intended to waive fully, and for the benefit of the parties hereto, any
rights and/or claims which might give rise to a right of subrogation in favor of
any insurance carrier. The coverage obtained by Subtenant pursuant to Section 12
of the Master Lease shall include, without limitation, a waiver of subrogation
endorsement attached to the certificate of insurance. The provisions of this
Section shall not apply in those instances in which such waiver of subrogation
would invalidate such insurance coverage or would cause either party's insurance
coverage to be voided or otherwise uncollectible.

     9.  Parking. Tenant shall have a license to use the number of
non-designated and non-exclusive parking spaces (as specified in the Basic
Sublease Information) within the designated Parking Area, as depicted in Exhibit
D attached hereto, on a "first come, first served basis" in common with other
tenants in the Building.

     10. Indemnity. Subtenant hereby agrees to indemnify and hold Tenant
harmless from and against any and all claims, losses and damages, including,
without limitation, reasonable attorneys' fees and disbursements, which may at
any time be asserted against Tenant by (a) the Landlord for failure of Subtenant
to perform any of the covenants, agreements, terms, provisions or conditions
contained in the Master Lease which, by reason of the provisions of this
Sublease, Subtenant is obligated to perform, and/or (b) any person by reason of
Subtenant's use and/or

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occupancy of the Sublease Premises, except to the extent any of the foregoing is
caused or by the negligence of Tenant. Tenant shall be responsible for any
actual costs reasonably incurred by Subtenant which arise out of Tenant's breach
of its obligations under the Master Lease with respect to the portion of the
Premises which are not part of the Sublease Premises after giving effect to
notice and cure periods, if any. The provisions of this Section 10 shall survive
the expiration or earlier termination of the Master Lease and/or this Sublease.

     11. Miscellaneous.

         (a) Entire Agreement. This Sublease contains all of the covenants,
conditions and agreements between the parties concerning the Sublease Premises,
and shall supersede all prior correspondence, agreements and understandings
concerning the Sublease Premises, both oral and written. No addition or
modification of any term or provision of this Sublease shall be effective unless
set forth in writing and signed by both Tenant and Subtenant, and consented to
in writing by Landlord.

         (b) Captions. All captions and headings in this Sublease are for the
purposes of reference and convenience and shall not limit or expand the
provisions of this Sublease.

         (c) Landlord's Consent. This Sublease is conditioned upon obtaining the
written consent of Landlord. If Landlord refuses to consent to this Sublease,
this Sublease shall terminate and neither party shall have any continuing
obligation to the other with respect to the Sublease Premises; provided Tenant
shall return the Security Deposit, if previously delivered to Tenant, to
Subtenant.

         (d) Authority. Each person executing this Sublease on behalf of a party
hereto represents and warrants that he or she is authorized and empowered to do
so and to thereby bind the party on whose behalf he or she is signing.

         (e) Attorneys' Fees. In the event either party shall bring any action
or proceeding for damages or for an alleged breach of any provision of this
Sublease to recover rents, or to enforce, protect or establish any right or
remedy hereunder, the prevailing party shall be entitled to recover reasonable
attorneys' fees and court costs as part of such action or proceeding.

         (f) Brokerage Commission. Tenant and Subtenant each represents and
warrants for the benefit of the other and Landlord that neither Tenant nor
Subtenant have had any dealings with any real estate broker, agent or finder in
connection with the Sublease Premises and/or the negotiation of this Sublease,
except for the Broker(s) (as set forth in the Defined Terms), and that neither
Tenant nor Subtenant knows of any other real estate broker, agent or finder who
is or might be entitled to a real estate brokerage commission or finder's fee in
connection with this Sublease or otherwise based upon contacts between the
claimant and either party. Tenant and Subtenant shall indemnify and hold
harmless the other from and against any and all liabilities or expenses arising
out of claims made for a fee or commission by any real estate broker, agent or
finder in connection with the Sublease Premises and this Sublease other than
Broker(s), if any, resulting from the actions of the indemnifying party.


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         IN WITNESS WHEREOF, the parties hereto have executed one (1) or more
copies of this Sublease, effective as of the Effective Date.

                                       TENANT:

                                       AUTODESK, INC., a Delaware corporation

                                       By: /s/ Steve Cakebread
                                          -----------------------------------

                                       Its: SRVP CFO
                                           -----------------------------------

                                       By:
                                          -----------------------------------

                                       Its:
                                           -----------------------------------


                                       SUBTENANT:

                                       OBJECTSWITCH CORPORATION, INC.,
                                       a California corporation

                                       By: /s/ Greg Straughn
                                          -----------------------------------

                                       Its: VP - Finance
                                           -----------------------------------

                                       By:
                                          -----------------------------------

                                       Its:
                                           -----------------------------------



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                                    EXHIBIT A

                         SUBLEASE PREMISES - FLOOR PLAN

                             [Intentionally Omitted.]



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                                    EXHIBIT B

                                  MASTER LEASE

                            [Intentionally Omitted.]



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                                    EXHIBIT C

                                  PARKING AREA

                              [Intentionally Omitted.]



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