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                                   Exhibit 2.5

                         COMMON STOCK PURCHASE AGREEMENT

                              E-SYNC NETWORKS, INC.

                                October 31, 2000
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                         COMMON STOCK PURCHASE AGREEMENT

         THIS COMMON STOCK PURCHASE AGREEMENT ("Agreement") is made as of the
31st day of October, 2000, by and between E-SYNC NETWORKS, INC. a Delaware
corporation (the "Company"), and David Mack (the "Investor").

                               W I T N E S S E T H

                  WHEREAS, the Company desires to issue and sell 540,541 shares
(the "Shares") of common stock, par value $0.01 per share, of the Company (the
"Common Stock") to the Investor; and

                  WHEREAS, the Investor desires to purchase the Shares, upon the
terms and conditions hereinafter set forth.

                  NOW, THEREFORE, in consideration of the premises and the
mutual covenants and representations hereinafter stated, and intending to be
legally bound hereby, the parties agree as follows:

         1.       Purchase and Sale of Shares.

                  1.1 Sale and Issuance of Shares. Subject to the terms and
conditions of this Agreement, including without limitation Sections 1.3 and 4
hereof, on the Closing Date (as defined below), at the Closing referred to in
Section 1.3 hereof (the "Closing"), the Investor agrees to purchase from the
Company and the Company agrees to sell and issue to the Investor, the Shares.

                  1.2 Purchase Price. As the full consideration to be paid by
the Investor for the issuance and sale of the Shares, the Investor shall pay to
the Company the aggregate sum of $1,000,000 (the "Purchase Price").

                  1.3 Closing.

                           (a) The Closing shall take place at the offices of
Finn Dixon & Herling LLP, Stamford, Connecticut, commencing at 9:00 a.m. Eastern
standard time on October 31, 2000, or on such other date as may be agreed to in
writing by the parties hereto (the "Closing Date").

                           (b) At the Closing the Company shall deliver to the
Investor a stock certificate or certificates representing the total number of
Shares to be issued and sold to the Investor.
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         2.       Representations of the Company.

                  2.1 Organization, Good Standing and Qualification. The Company
is a corporation duly organized, validly existing and in good standing under the
laws of the State of Delaware and has all requisite corporate power and
authority to carry on its business as now conducted and as proposed to be
conducted. The Company is duly qualified to transact business and is in good
standing in each jurisdiction in which the failure to so qualify would have a
material adverse effect on its business or properties.

                  2.2 Authorization. All corporate action on the part of the
Company, its officers, directors and stockholders necessary for the
authorization, execution and delivery of this Agreement, the performance of all
obligations of the Company hereunder, and the authorization, issuance (or
reservation for issuance), sale and delivery of the Shares being sold hereunder,
has been taken or will be taken prior to the Closing, and this Agreement
constitutes a valid and legally binding obligation of the Company, enforceable
in accordance with its terms.

                  2.3 Valid Issuance of the Securities. The Shares that are
being purchased by the Investor hereunder, when issued, sold and delivered in
accordance with the terms of this Agreement for the consideration expressed
herein, will be duly and validly issued, fully paid and nonassessable, and will
be free of restrictions on transfer other than restrictions on transfer under
this Agreement and under applicable state and federal securities laws.

                  2.4 Offering. Subject in part to the truth and accuracy of the
Investor's representations set forth in Section 3 of this Agreement, the offer,
sale and issuance of the Shares as contemplated by this Agreement are exempt
from the registration requirements of any applicable state and federal
securities laws, and neither the Company nor any authorized agent acting on its
behalf will take any action hereafter that would cause the loss of such
exemption.

                  2.5 SEC Reporting. The Company has filed all reports,
registration statements, definitive proxy statements and other documents and all
amendments thereto and supplements thereof required to be filed by it with the
United States Securities and Exchange Commission (the "SEC") since October 31,
1999 (the "SEC Reports"), all of which have complied in all material respects
with all applicable requirements of the Securities Act of 1933, as amended (the
"Act"), and the Securities Exchange Act of 1934, as amended, and the rules and
regulations promulgated thereunder. As of the respective dates of filing in
final or definitive form (or, if amended or superseded by a subsequent filing,
then on the date of such subsequent filing), none of the Company's SEC Reports
contained any untrue statement of a material fact or omitted to state a material
fact required to be stated therein or necessary in order to make the statements
therein, in light of the circumstances in which they were made, not misleading.

         3.       Representations and Warranties of the Investors. The Investor
hereby represents and warrants to the Company and acknowledges and intends that
the Company rely thereon, as follows:
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                  3.1 Investment. The Investor is acquiring the Shares for his
own account for investment and not with a view to, or for sale in connection
with, any distribution thereof, nor with any present intention of distributing
or selling the same; and, except as contemplated by this Agreement, the Investor
has no present or contemplated agreement, undertaking, arrangement, obligation,
indebtedness or commitment providing for the disposition thereof. The Investor
is an "accredited investor" as defined in Rule 501(a) under the Act. The
Investor understands that the Shares have not been, and will not be, registered
under the Act by reason of a specific exemption from the registration provisions
of the Act, the availability of which depends upon, among other things, the bona
fide nature of the investment intent and the accuracy of the Investor's
representations as expressed herein.

                  3.2 Authority. The Investor has full power and authority to
enter into and to perform this Agreement in accordance with its terms.

                  3.3 Experience. The Investor has reviewed the representations
concerning the Company contained in this Agreement carefully and has made
detailed inquiry concerning the Company, its business and its personnel; the
officers of the Company have made available to the Investor any and all written
information which he has requested and have answered to the Investor's
satisfaction all inquiries made by the Investor; and the Investor has sufficient
knowledge and experience in finance and business that he is capable of
evaluating the risks and merits of his investment in the Company and the
Investor financially is able to bear the risks thereof.

                  3.4 Legend. The Investor understands that the certificates
evidencing the Shares will bear a legend stating in substance the foregoing and
the Investor agrees to the foregoing:

         THE SALE AND ISSUANCE OF THE SHARES REPRESENTED BY THIS CERTIFICATE
         HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED,
         OR UNDER THE SECURITIES LAW OF ANY STATE OR OTHER JURISDICTION. THESE
         SHARES HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO, OR IN
         CONNECTION WITH, THE DISTRIBUTION THEREOF. THESE SHARES MAY NOT BE
         OFFERED, SOLD, PLEDGED, OR TRANSFERRED UNLESS (I) A REGISTRATION
         STATEMENT UNDER THE ACT IS IN EFFECT AS TO THESE SHARES AND SUCH OFFER,
         SALE, PLEDGE, OR TRANSFER IS IN COMPLIANCE WITH APPLICABLE SECURITIES
         LAW OF ANY STATE OR OTHER JURISDICTION OR (II) THERE IS AN OPINION OF
         COUNSEL OR OTHER EVIDENCE, SATISFACTORY TO THE COMPANY, THAT AN
         EXEMPTION THEREFROM IS AVAILABLE AND THAT SUCH OFFER, SALE, PLEDGE, OR
         TRANSFER IS IN COMPLIANCE WITH APPLICABLE SECURITIES LAW OF ANY STATE
         OR OTHER JURISDICTION.
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         4.       Condition to Closing. The obligation of the Company to issue
and sell the Shares to the Investor shall be conditioned upon the payment of the
Purchase Price by the Investor to the Company on or before the Closing.

         5.       Miscellaneous.

                  5.1 Survival of Warranties. The warranties, representations
and covenants of the Company and the Investor contained in or made pursuant to
this Agreement shall survive the execution and delivery of this Agreement and
the Closing for a period of one year thereafter and shall in no way be affected
by any investigation of the subject matter thereof made by or on behalf of the
Investor or the Company.

                  5.2 Successors and Assigns. The terms and conditions of this
Agreement shall inure to the benefit of and be binding upon the respective
successors and assigns of the parties hereto. Nothing in this Agreement, express
or implied, is intended to confer upon any party other than the parties hereto
or their respective successors and assigns any rights, remedies, obligations, or
liabilities under or by reason of this Agreement, except as expressly provided
in this Agreement.

                  5.3 Governing Law. This Agreement shall be governed by and
construed under the laws of the State of Connecticut, as applied to agreements
among Connecticut residents entered into and to be performed entirely within
Connecticut.

                  5.4 Counterparts. This Agreement may be executed in two or
more counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

                  5.5 Titles and Subtitles. The titles and subtitles used in
this Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.

                  5.6 Notices. Unless otherwise provided, any notice required or
permitted under this Agreement shall be given in writing and shall be deemed
effectively given (i) upon personal delivery to the party to be notified, (ii)
forty-eight (48) hours after deposit with the United States Post Office, by
registered or certified mail, postage prepaid and addressed to the party to be
notified at the address indicated for such party on the signature page hereof,
or at such other address as such party may designate by ten (10) days' advance
written notice to the other parties, (iii) upon transmission of a confirmed
telecopy to such party at a telecopier number furnished by such party for such
purpose, or (iv) upon delivery to such address by Federal Express or other
overnight courier service.

                  5.7 Amendments and Waivers. Any term of this Agreement may be
amended and the observance of any term of this Agreement may be waived (either
generally or in a
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particular instance and either retroactively or prospectively), only with the
written consent of the Company and the Investor.

                  5.8 Severability. If one or more provisions of this Agreement
are held to be unenforceable under applicable law, such provision shall be
excluded from this Agreement and the balance of the Agreement shall be
interpreted as if such provision were so excluded and shall be enforceable in
accordance with its terms.

                  5.9 Remedies. Each of the parties to this Agreement is
entitled to all remedies in the event of breach provided at law or in equity,
specifically including, but not limited to, specific performance.

                  5.10 Nouns and Pronouns. Whenever the context may require, any
pronouns used herein shall include the corresponding masculine, feminine or
neuter forms, and the singular form of names and pronouns shall include the
plural and vice versa.

                  5.11 Information to be Provided by Investor. The Investor
agrees to provide to the Company such information as the Company reasonably may
request in order to make accurate and timely required filings and disclosures to
its stockholders and to federal, state and self-regulatory agencies.
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         Company                       E-Sync Networks, Inc
                                       35 Nutmeg Drive
                                       Trumbull, CT 06611

                                       By: /s/ Frank J. Connolly Jr.
                                           -------------------------

         Investor                      /s/ David Mack
                                       ----------------------------
                                       David Mack
                                       c/o The Mack Company
                                       370 West Passaic Street
                                       Rochelle Park, NJ 07662