SECURITIES AND EXCHANGE COMMISSION
                                                        WASHINGTON, DC 20549


                                                             FORM 8-A/A
                                                           AMENDMENT NO. 2


                                          FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                                               PURSUANT TO SECTION 12(B) OR (G) OF THE
                                                   SECURITIES EXCHANGE ACT OF 1934


                                                       MERCATOR SOFTWARE, INC.
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                                       (Exact Name of Registrant as Specified in its Charter)


                            DELAWARE                                                            06-1132156
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            (State of Incorporation or Organization)                                         (I.R.S. Employer
                                                                                            Identification No.)


                  45 DANBURY ROAD, WILTON, CT                                                     06897
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            (Address of Principal Executive Offices                                             (Zip Code)



If this Form relates to the registration of a class of                 If this Form relates to the registration of a class of
securities pursuant to Section 12(b) of the Exchange Act and           securities pursuant to Section 12(g) of the Exchange Act and
is effective pursuant to General Instruction A.(c), please             is effective pursuant to General Instruction A.(d), please
check the following box. |_|                                           check the following box. |X|



Securities Act registration statement file number to which this form relates:                                      NONE
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Securities to be registered pursuant to Section 12(b) of the Act:                                                  NONE
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Securities to be registered pursuant to Section 12(g) of the Act:


                                                   PREFERRED STOCK PURCHASE RIGHTS
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                                                          (Title of Class)




       On September 4, 1998, Mercator Software, Inc., a Delaware corporation
formerly known as TSI International Software LTD. ("Mercator"), filed a
Registration Statement on Form 8-A with the Securities and Exchange Commission
(the "SEC") relating to the Rights Agreement dated as of September 2, 1998
between Mercator and The Bank of New York, as Rights Agent (the "Rights Agent").
On January 13, 2003, Mercator filed an amendment to such Registration Statement
on Form 8-A with the SEC relating to an amendment to such Rights Agreement dated
as of January 8, 2003 (such Rights Agreement, as so amended, the "Rights
Agreement"). The Registration Statement on Form 8-A filed by Mercator on
September 4, 1998, as amended on January 13, 2003 is referred to as the "Form
8-A."

ITEM 1.       DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED.

       Item 1 of the Form 8-A is amended and supplemented by adding the
following:

       On August 2, 2003, Mercator entered into an Agreement and Plan of Merger
(the "Merger Agreement") with Ascential Software Corporation, a Delaware
corporation ("Parent"), and Greek Acquisition Corporation, a Delaware
corporation and a wholly-owned subsidiary of Parent ("Sub"), providing for,
among other things: (i) an offer (the "Offer") by Sub to purchase all of
Mercator's outstanding common stock, par value $0.01 per share, and the
associated preferred stock purchase rights (collectively, the "Shares"); and
(ii) following consummation of the Offer, the merger (the "Merger") of Sub with
and into Mercator.

       Prior to the execution and delivery of the Merger Agreement, Mercator and
the Rights Agent entered into the Second Amendment (the "Amendment") to the
Rights Agreement in order to exempt the Offer and the Merger and related
transactions from the Rights Agreement and to provide that the Rights (as
defined in the Rights Agreement) will expire immediately prior to the
consummation of the Merger.

       Among other things, the Amendment:

       (i)    amends the definition of "Acquiring Person" set forth in the
              Rights Agreement to provide that:

              (A)    neither Parent, Sub nor any of their respective Affiliates
                     or Associates (as defined in the Rights Agreement) shall be
                     deemed to be an Acquiring Person solely by virtue of: (x)
                     the execution and delivery of the Merger Agreement or the
                     Option Agreement (as defined in the Merger Agreement); (y)
                     the acquisition of Shares pursuant to the Merger Agreement
                     or the Option Agreement; or (z) the consummation of the
                     other transactions contemplated in the Merger Agreement or
                     the Option Agreement; and

              (B)    neither Parent, Sub, any other party to the Stock Tender
                     Agreement (as defined in the Merger Agreement) nor any of
                     their respective Affiliates or Associates shall be deemed
                     to be an Acquiring Person solely by virtue of: (x) the
                     execution and delivery of the Stock Tender Agreement; or
                     (y) any actions taken or effected pursuant to the Stock
                     Tender Agreement;

       (ii)   amends the definition of "Final Expiration Date" set forth in the
              Rights Agreement to mean the earlier to occur of: (x) the close of
              business on September 2, 2008; or (y) the time immediately prior
              to the Effective Time (as defined in the Merger Agreement); and

       (iii)  amends the "flip-in" and "flip-over" provisions set forth in
              Sections 11 and 13, respectively, of the Rights Agreement in order
              to exempt the Offer and the Merger and related transactions from
              the Rights Agreement.

       A copy of the Amendment is attached hereto as Exhibit 4.3 and is
incorporated herein by



reference. The foregoing description of the Amendment does not purport to be
complete and is qualified in its entirety by reference to the Amendment.

ITEM 2.       EXHIBITS.

       The documents listed below are filed as exhibits to this registration
statement:

EXHIBIT NO.      DESCRIPTION
-----------      -----------

       3.1    Amended and Restated Certificate of Incorporation of the
              registrant (included as Exhibit 3.1 to the Quarterly Report on
              Form 10-Q for the quarter ended September 30, 2000 filed by the
              registrant with the SEC on November 14, 2000 and incorporated
              herein by reference)
       3.2    Amended and Restated Bylaws of the registrant (included as Exhibit
              3.1 to the Current Report on Form 8-K filed by the registrant with
              the SEC on September 4, 1998 and incorporated herein by reference)
       3.3    Certificate of Designations specifying the terms of the Series A
              Junior Participating Preferred Stock of the registrant (included
              as Exhibit 3.2 to the Registration Statement on Form 8-A filed by
              the registrant with the SEC on September 4, 1998 and incorporated
              herein by reference)
       4.1    Rights Agreement dated as of September 2, 1998 between TSI
              International Software LTD. (now known as Mercator Software, Inc.)
              and The Bank of New York, as Rights Agent, which includes as
              Exhibit A the form of Certificate of Designations of Series A
              Junior Participating Preferred Stock, as Exhibit B the Form of
              Right Certificate and as Exhibit C the Summary of Rights to
              Purchase Preferred Shares (included as Exhibit 4.1 to the
              Registration Statement on Form 8-A filed by the registrant with
              the SEC on September 4, 1998 and incorporated herein by reference)
       4.2    Amendment to Rights Agreement dated as of January 8, 2003 between
              the registrant and The Bank of New York, as Rights Agent (included
              as Exhibit 4.1 to Amendment No. 1 to the Registration Statement on
              Form 8-A filed by the registrant with the SEC on January 13, 2003
              and incorporated herein by reference)
       4.3    Second Amendment to Rights Agreement dated as of August 2, 2003
              between the registrant and The Bank of New York, as Rights Agent
              (included as Exhibit 3 to the Current Report on Form 8-K dated
              (date of earliest event reported) August 2, 2003 filed by the
              registrant with the SEC on August 4, 2003 and incorporated herein
              by reference)


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                                    SIGNATURE

       Pursuant to the requirements of Section 12 of the Securities Exchange Act
of 1934, the registrant has duly caused this registration statement to be signed
on its behalf by the undersigned, thereto duly authorized.

Dated:  August 4, 2003

                                   MERCATOR SOFTWARE, INC.


                                   By:   /s/ Roy C. King
                                       ----------------------------------------
                                         Chairman of the Board of Directors,
                                          Chief Executive Officer and President




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                                       EXHIBIT INDEX

EXHIBIT NO.   DESCRIPTION                                                              PAGE NO.
-----------   -----------                                                              --------

       3.1    Amended and Restated Certificate of Incorporation of the
              registrant (included as Exhibit 3.1 to the Quarterly Report on
              Form 10-Q for the quarter ended September 30, 2000 filed by the
              registrant with the SEC on November 14, 2000 and incorporated
              herein by reference)
       3.2    Amended and Restated Bylaws of the registrant (included as Exhibit
              3.1 t the Current Report on Form 8-K filed by the registrant with
              the SEC on September 4, 1998 and incorporated herein by reference)
       3.3    Certificate of Designations specifying the terms of the Series A
              Junior Participating Preferred Stock of the registrant (included
              as Exhibit 3.2 to the Registration Statement on Form 8-A filed by
              the registrant with the SEC on September 4, 1998 and incorporated
              herein by reference)
       4.1    Rights Agreement dated as of September 2, 1998 between TSI
              International Software LTD. (now known as Mercator Software, Inc.)
              and The Bank of New York, as Rights Agent, which includes as
              Exhibit A the form of Certificate of Designations of Series A
              Junior Participating Preferred Stock, as Exhibit B the Form of
              Right Certificate and as Exhibit C the Summary of Rights to
              Purchase Preferred Shares (included as Exhibit 4.1 to the
              Registration Statement on Form 8-A filed by the registrant with
              the SEC on September 4, 1998 and incorporated herein by reference)
       4.2    Amendment to Rights Agreement dated as of January 8, 2003 between
              the registrant and The Bank of New York, as Rights Agent (included
              as Exhibit 4.1 to Amendment No. 1 to the Registration Statement on
              Form 8-A filed by the registrant with the SEC on January 13, 2003
              and incorporated herein by reference)
       4.3    Second Amendment to Rights Agreement dated as of August 2, 2003
              between the registrant and The Bank of New York, as Rights Agent
              (included as Exhibit 3 to the Current Report on Form 8-K dated
              (date of earliest event reported) August 4, 2003 filed by the
              registrant with the SEC on August 4, 2003 and incorporated herein
              by reference)