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                                                                   EXHIBIT 10.56


                FIRST AMENDMENT TO STOCK RESTRICTION AGREEMENT
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          THIS FIRST AMENDMENT TO STOCK RESTRICTION AGREEMENT (this "Amendment")
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is made as of March 23, 2000, between ZEFER Corp., a Delaware corporation (the
"Company"), and David Lubin ("Holder").  Except as otherwise indicated herein,
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capitalized terms used and not otherwise defined herein shall have the meanings
ascribed to such terms in the Purchase Agreement (as defined below).

          WHEREAS, the parties to this Amendment are all of the parties to that
certain Stock Restriction Agreement, dated as of March 23, 1999, between the
Company and Holder (the "Stock Restriction Agreement");
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          WHEREAS, the parties hereto desire to make certain amendments to the
Purchase Agreement in accordance with Section 12(i) thereof; and

          NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

Section 1.  Amendments to Stock Restriction Agreement.
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       1A.  Section 2(a) of the Stock Restriction Agreement shall be amended and
restated in its entirety as follows:

            (a)  All of the shares of Holder Stock acquired hereunder shall be
     subject to vesting in the manner specified in this Section 2. Except as
     otherwise provided in Sections 2(b) and 2(c) below, commencing on the day
     immediately following the Closing and continuing so long as Holder is still
     serving as a director of the Company or any of its Subsidiaries,
     the Holder Stock will vest daily on a pro rata basis so that 100% of the
     Holder Stock will be vested on the 5th Anniversary of the Closing (the
     "Vesting Schedule").
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       1B.  Section 2(b) of the Stock Restriction Agreement shall be amended and
     restated in its entirety as follows:

            (b)  In the event the Company consummates its initial Public
     Offering prior to the 1st Anniversary of the Closing, the Vesting Schedule
     shall be modified such that, so long as Holder is still serving as a
     director of the Company or any of its Subsidiaries, the shares
     of Holder Stock will vest as follows: (i) 33% of the Holder Stock will vest
     upon the occurrence of such Public Offering, and (ii) commencing on the day
     immediately following such Public Offering, the remaining unvested shares
     of Holder Stock will vest daily on a pro rata basis so that 100% of the
     Holder Stock will be vested on the 5th Anniversary of the Closing. In the
     event the Company consummates its initial Public Offering after the 1st
     Anniversary of the Closing but prior to the 2nd Anniversary of the Closing,
     the Vesting Schedule shall be modified such that, so long as Holder is
     still serving as a director of the Company or any of its Subsidiaries, the
     shares of Holder Stock that are unvested immediately prior to such initial
     Public Offering will vest as follows: (i) an additional number of shares of
     Holder
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     Stock will vest upon the occurrence of such Public Offering so that 33% of
     the Holder Stock will be vested immediately thereafter, (ii) commencing on
     the day immediately following such Public Offering and continuing until the
     2nd Anniversary of the Closing, an additional number of shares of Holder
     Stock will vest daily on a pro rata basis so that 40% of the Holder Stock
     will be vested on the 2nd Anniversary of the Closing, and (iii) commencing
     on the day immediately following the 2nd Anniversary of the Closing, the
     remaining unvested shares of Holder Stock will vest daily on a pro rata
     basis so that100% of the Holder Stock will be vested on the 5th Anniversary
     of the Closing.

            Section 2.  Retroactive Application of Amended and Restated Vesting
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Schedule. The amendment set forth in Section 1A above shall be applied
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retroactively so as to cause the Holder Stock to be subject to the amended and
restated Vesting Schedule as of May 21, 1999.

            Section 3.  Limitations.  Except as expressly amended by this
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Amendment, all of the terms and provisions of the Stock Restriction Agreement
shall remain in full force and effect. This Amendment supersedes and preempts
any prior understandings, agreements or representations by or between the
parties, written or oral, which may have related to the subject matter hereof in
any way.


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          IN WITNESS WHEREOF, the parties hereto have executed this First
Amendment to Stock Restriction Agreement on the date first written above.

                                        ZEFER Corp.
                                        By:  /s/ James Slamp
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                                        Its:  President
                                             /s/ David Lubin
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                                              David Lubin

Agreed and Accepted:

GTCR FUND VI, L.P.
By:       GTCR Partners VI, L.P.
Its:      General Partner
By:       GTCR Golder Rauner, L.L.C.
Its:      General Partner

By:       /s/ Philip Canfield
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Name:
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Its:      Principal

GTCR VI EXECUTIVE FUND, L.P.
By:       GTCR Partners VI, L.P.
Its:      General Partner
By:       GTCR Golder Rauner, L.L.C.
Its:      General Partner

By:       /s/ Philip Canfield
     ----------------------------------------
Name:
     ----------------------------------------
Its:      Principal

GTCR ASSOCIATES VI
By:       GTCR Partners VI, L.P.
Its:      General Partner
By:       GTCR Golder Rauner, L.L.C.
Its:      General Partner

By:       /s/ Philip Canfield
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Name:
     ----------------------------------------
Its:      Principal

                       SIGNATURE PAGE TO FIRST AMENDMENT
                        TO STOCK RESTRICTION AGREEMENT