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                                                                    EXHIBIT 10.5

                              AMENDED AND RESTATED
                          STOCK RESTRICTION AGREEMENT

     This Agreement is made effective the 24th day of January, 2000, between
SupplierMarket.com, Inc., a Delaware corporation (the "Company"), and
                                                       -------
Jonathan Burgstone (the "Employee").
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     WHEREAS, the Employee owns 9,318,000 shares (the "Shares") of the
                                                       ------
Company's Common Stock, par value $.001 per share (the "Common Stock") which he
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acquired for a purchase price of $.001 per share, of which 5,823,750 of the
Shares have vested and are no longer subject to repurchase by the Company upon
execution of this Agreement;

     WHEREAS, the Company and the Employee entered into a Stock Restriction
Agreement dated June 28, 1999 (the "Stock Restriction Agreement");
                                    ----------------------------

     WHEREAS, in recognition of the Employee's contributions to the successful
launch of the Company's business and the Employee's contributions to the
consummation of the Company's Series B preferred stock financing, the Company
and the Employee have agreed to (a) enter into an employment agreement
(the "Employment Agreement") and (b) amend certain provisions of the Stock
      --------------------
Restriction Agreement;

     WHEREAS, the Company and the Employee desire to set forth their agreement
regarding the amendment of the Stock Restriction Agreement as hereinafter
provided;

     NOW, THEREFORE, in consideration of the mutual promises and covenants
contained in this Agreement, and for other valuable consideration, receipt of
which is hereby acknowledged, the parties hereto agree as follows:

     1.   Option of Company upon Termination of Employment.
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          a.   In the event that the Employee shall cease to be employed by the
Corporation (including a parent or subsidiary of the Company) for any or no
reason, including, without limitation, death, disability, or involuntary removal
with or without Cause, the Company shall have the right and option (the

"Purchase Option"), within 60 days after the date that the Employee ceases to be
----------------
employed by the Company, to purchase from the Employee at the purchase price per
share ($.001) paid therefor by the Employee (the "Purchase Price"), up to
3,495,250 Shares (such number of Shares being subject to equitable adjustment
for any stock split, stock dividend, combination of shares or the like based
upon Common Stock or Common Stock equivalents), other than any of such Shares
which become Vested Shares, as defined in Section 1(b).
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          b.   "Vested Shares" shall mean the product obtained by multiplying
3,495,250 Shares by a fraction, the numerator of which is the number of calendar
months from January 1, 2000 (the "Commencement Date") to the end of the calendar
month during which the Employee ceases to be employed by the Company, and the
denominator of which is 18, provided, however, in the event that the Employee is
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terminated or discharged without Cause by the Company, or the Employee resigns
for Good Reason (i) prior to June 28, 2000, such numerator shall be the number
of calendar months from the Commencement Date to the Termination Date plus
twelve, or (ii) after June 28, 2000, all of the remaining Shares covered hereby
shall immediately become Vested Shares.

     For purposes of this Section 1(b), the following definitions shall apply:

          (a)  "Cause" shall mean (i) the commission by the Employee of any
     embezzlement or other deliberate and premeditated act of dishonesty against
     the financial or business interests of the Company; (ii) the habitual drug
     addiction or intoxication of the Employee; (iii) the conviction by the
     Employee of, or the pleading by the Employee of nolo contendere to, a
     felony; (iv) the willful failure or refusal of the Employee to carry out
     the duties of the Employee or to follow reasonable directives of the Board
     of Directors which failure or refusal is not cured within 30 days
     subsequent to written notice from the Company to the Employee; or (v) the
     material breach by the Employee of this Agreement or the Employment
     Agreement.

          (b)  "Good Reason" shall mean any of the following: (i) a material
     diminution in the Employee's responsibilities, duties or authority, which
     shall include but not be limited to the demotion of the Employee below the
     level of Executive Vice President, to which the Employee has not consented
     and which remains unremedied for 10 days after the receipt by the Company's
     Board of Directors of written notice thereof from the Employee (it being
     understood that the Company's demotion of the Employee from the position of
     CEO as a result of the hiring of another CEO shall not by itself be
     considered a "material diminution" in his responsibilities); (ii) any other
     action taken in bad faith by the Company for the purpose of interfering
     with the performance of the responsibilities of the Employee, if such
     action in fact materially and adversely affects the performance of such
     responsibilities, and which remains unremedied for 10 days after the
     receipt by the Company's Board of Directors of written notice thereof from
     the Employee; (iii) the relocation of the Employee by the Company outside
     the Company's main office without the Employee's written consent; or (iv) a
     decrease in the Employee's compensation without the Employee's written
     consent.

          (c)  If the Company desires to exercise its Purchase Option, it shall
do so by communicating in writing its election to purchase to the Employee,
which communication shall state the number of Shares the Company is electing to
purchase and shall be delivered in person or mailed to the Employee at the
address set forth on the signature page hereto. The sale of the Shares to be
sold to the Company pursuant to this Section 1 shall be made at the offices of
the
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Company on the 20th day following the date of the Company's written election to
purchase (or if such 20th day is not a business day, then on the next succeeding
business day). Such sale shall be effected by the Employee's delivery to the
Company of a certificate or certificates evidencing the Shares to be purchased
by it, duly endorsed for transfer to the Company, against payment to the
Employee by the Company at the Option Price for each Share to be purchased by
the Company.

          (d)  The Employee agrees not to transfer any Shares if, on the date of
such transfer, such Shares do not constitute "Vested Shares" as defined above.

          (e)  If the Employee becomes obligated to sell any Shares to the
Company under this Agreement and fails to deliver such Shares in accordance with
the terms of this Agreement, the Company may, at its option, in addition to all
other remedies it may have, send to the Employee the Purchase Price for such
Shares as herein specified. Thereafter, the Company upon written notice to the
Employee, (i) shall cancel on its books the certificate or certificates
representing the Shares to be sold and (ii) shall issue, in lieu thereof, in the
name of the Company a new certificate or certificates representing such Shares,
and thereupon all of the Employee's rights in and to such Shares shall
terminate.

     2.   Legends.  The certificate(s) representing the Shares will bear the
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following legend with respect to the foregoing:

     The shares of stock represented by this certificate are subject to an
     option to purchase such shares and certain restrictions upon transfer
     contained in a certain Amended and Restated Stock Restriction Agreement,
     dated as of January __, 2000, a copy of which the Company will furnish to
     the holder of this certificate upon request and without charge.

     3.  Rights as Stockholder.  Subject to the provisions of this Agreement,
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the Employee shall, during the term of this Agreement, exercise all rights and
privileges of a stockholder of the Company.

     4.   Continuation of Employment.  Nothing in this Agreement shall create
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an obligation on the Company to continue the Employee's employment with the
Company.

     5.   Notices.  Any notice required or permitted hereunder shall be given
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in writing and shall be deemed effectively given upon personal delivery or upon
deposit in the United States mail by registered or certified mail with postage
and fees prepaid, addressed to the other party hereto, if to the Employee, at
the Employee's residence address as reflected on the records of the Company, and
if to the Company, at the address of its principal offices on the date upon
which such notice is given.
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     6.   Entire Agreement and Amendment.  This Agreement constitutes the entire
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agreement of the parties with respect to the subject matter hereof and neither
this Agreement nor any provision hereof may be waived, modified, amended or
terminated except by a written agreement signed by the parties hereto. This
Agreement is the sole agreement to which the Employee is a party regarding the
subject matter hereof and supersedes any prior agreements between the Employee
and the Company as to such subject matter.

     7.   Dispute Resolution.  Any controversy or claim arising out of or
          ------------------
relating to this Agreement, or the breach thereof, shall be submitted to and
determined by a single arbitrator in the city of Boston, Massachusetts in
accordance with the rules of the American Arbitration Association, and judgment
upon the award shall be final, binding, and conclusive upon the parties and may
be entered in any court having competent jurisdiction thereof.

     8.   Specific Performance.  Without intending to limit the remedies
                  ------------
available to the Company, the Employee agrees that damages at law will be an
insufficient remedy to the Company in the event that the Employee violates the
terms of this Agreement and that the Company may apply for and obtain immediate
injunctive relief in any court of competent jurisdiction or restrain the breach
or threatened breach of, or otherwise to specifically enforce, any of the
agreements and covenants contained in this Agreement.

     9.   Governing Law.  This Agreement shall be governed by and construed in
                   ----
accordance with the internal laws of The Commonwealth of Massachusetts without
regard to the conflict of laws provisions thereof

     10.  This Agreement hereby supersedes the Stock Restriction Agreement in
its entirety.

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                                                   [Stock Restriction Agreement]

     This Agreement shall take effect as an instrument under seal, and shall be
binding upon the heirs, personal representatives, successors and assigns of the
Employee.

                                            SUPPLIERMARKET.COM, INC.



                                            By: /s/ Asif Satchu
                                                ------------------------
                                                Name: Asif Satchu
                                                Title: President


                                            EMPLOYEE:


                                            /s/ Jonathan Burgstone
                                            ----------------------------
                                            Jonathan Burgstone