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                                                                    Exhibit 10.5


                       FORM OF NEGATIVE PLEDGE AGREEMENT

         This Negative Pledge Agreement is made as of January 30, 2003, by and
between _________________ with offices at _______________________("Borrower")
and SILICON VALLEY BANK, a California-chartered bank, with its principal place
of business at 3003 Tasman Drive, Santa Clara, California 95054 and with a loan
production office located at One Newton Executive Park, Suite 200, 2221
Washington Street, Newton, Massachusetts 02462, doing business under the name
"Silicon Valley East" ("Bank").

In connection with, among other documents, the Loan and Security Agreement (the
"Loan Documents") being concurrently executed herewith between Borrower and
Bank, Borrower agrees as follows:

         1. Except (i) for the granting of non-exclusive licenses or sublicenses
            by Borrower in the ordinary course of business, (ii) as otherwise
            permitted in the Loan Documents and (iii) entering into escrow and
            similar arrangements with respect to source code in the ordinary
            course of business, Borrower has not, and shall not, sell, transfer,
            assign, mortgage, pledge, lease, grant a security interest in, or
            encumber any of Borrower's Intellectual Property (as defined below).

         2. As of the date hereof, Borrower has not, and from and after the date
            hereof shall not, enter into a negative pledge agreement, or similar
            agreement, affecting the rights of the Intellectual Property with
            any other party.

         3. It shall be an event of default under the Loan Documents between
            Borrower and Bank if there is a breach of any term of this Negative
            Pledge Agreement.

         4. As used herein,

            a. "Intellectual Property" means:

                (i)   Any and all Copyrights;

                (ii)  Any and all trade secrets, and any and all intellectual
                      property rights in computer software and computer software
                      products now or hereafter existing, created, acquired or
                      held;

                (iii) Any and all design rights which may be available to
                      Borrower now or hereafter existing, created, acquired or
                      held;

                (iv)  All Mask Works or similar rights available for the
                      protection of semiconductor chips;

                (v)   All Patents;

                (vi)  Any Trademarks;

                (vii) Any and all claims for damages by way of past, present and
                      future infringements of any of the rights included above,
                      with the right, but not the obligation, to sue for and
                      collect such damages for said use or infringement of the
                      intellectual property rights identified above;

                (viii) All licenses or other rights to use any of the
                      Copyrights, Patents, Trademarks, or Mask Works and all
                      license fees and royalties arising from such use to the
                      extent permitted by such license or rights; and

                (ix)  All amendments, extensions, renewals and extensions of any
                      of the Copyrights, Trademarks, Patents, or Mask Works; and

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                (x)   All proceeds and products of the foregoing, including
                      without limitation all payments under insurance or any
                      indemnity or warranty payable in respect of any of the
                      foregoing.

            b. "Copyrights" means any and all copyright rights, copyright
               applications, copyright registrations and like protections in
               each work of authorship and derivative work thereof, whether
               published or unpublished and whether or not the same also
               constitutes a trade secret, now or hereafter existing, created,
               acquired or held.

            c. "Mask Works" means all mask work or similar rights available for
               the protection of semiconductor chips, now owned or hereafter
               acquired;

            d. "Patents" means all patents, patent applications and like
               protections including without limitation improvements, divisions,
               continuations, renewals, reissues, extensions and
               continuations-in-part of the same.

            e. "Trademarks" means any trademark and servicemark rights, whether
               registered or not, applications to register and registrations of
               the same and like protections, and the entire goodwill of the
               business of Borrower connected with and symbolized by such
               trademarks.

         5. Capitalized terms used but not otherwise defined herein shall have
            the same meaning as in the Loan Documents.

         6. The laws of the Commonwealth of Massachusetts shall apply to this
            Agreement. BORROWER AND BANK EACH ACCEPTS FOR ITSELF AND IN
            CONNECTION WITH ITS PROPERTIES, UNCONDITIONALLY, THE NON-EXCLUSIVE
            JURISDICTION OF ANY STATE OR FEDERAL COURT OF COMPETENT JURISDICTION
            IN THE COMMONWEALTH OF MASSACHUSETTS IN ANY ACTION, SUIT, OR
            PROCEEDING OF ANY KIND, AGAINST IT WHICH ARISES OUT OF OR BY REASON
            OF THIS AGREEMENT; PROVIDED, HOWEVER, THAT IF FOR ANY REASON BANK
            CANNOT AVAIL ITSELF OF THE COURTS OF THE COMMONWEALTH OF
            MASSACHUSETTS, BORROWER ACCEPTS JURISDICTION OF THE COURTS AND VENUE
            IN SANTA CLARA COUNTY, CALIFORNIA. NOTWITHSTANDING THE FOREGOING,
            THE BANK SHALL HAVE THE RIGHT TO BRING ANY ACTION OR PROCEEDING
            AGAINST THE BORROWER OR ITS PROPERTY IN THE COURTS OF ANY OTHER
            JURISDICTION WHICH THE BANK DEEMS NECESSARY OR APPROPRIATE IN ORDER
            TO REALIZE ON THE COLLATERAL OR TO OTHERWISE ENFORCE THE BANK'S
            RIGHTS AGAINST THE BORROWER OR ITS PROPERTY.

         7. This Agreement shall become effective only when it shall have been
            executed by Borrower and Bank.

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         EXECUTED as a sealed instrument under the laws of the Commonwealth of
Massachusetts as of the date first written above.

                                  BORROWER:

                                  [NAME]

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

                                  Name:
                                       ----------------------------------------

                                  Title:
                                        ---------------------------------------

                                  BANK:

                                  SILICON VALLEY BANK D/B/A SILICON VALLEY EAST

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

                                  Name:
                                       ----------------------------------------

                                  Title:
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