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                                                                    EXHIBIT 32.1

                   INTERNATIONAL BUSINESS MACHINES CORPORATION

                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

     In connection with the Quarterly Report of International Business Machines
Corporation (the "Company") on Form 10-Q for the period ending June 30, 2003 as
filed with the Securities and Exchange Commission on the date hereof (the
"Report"), I, Samuel J. Palmisano, Chairman, President and Chief Executive
Officer of the Company, certify, pursuant to 18 U.S.C. ss. 1350, as adopted
pursuant to ss. 906 of the Sarbanes-Oxley Act of 2002, that:

   (1) The Report fully complies with the requirements of section 13(a) or 15(d)
of the Securities Exchange Act of 1934; and

   (2) The information contained in the Report fairly presents, in all material
respects, the financial condition and results of operations of  the Company.

/s/ Samuel J. Palmisano
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    Samuel J. Palmisano
    Chairman, President and Chief Executive Officer
    August 14, 2003


A signed original of this written statement required by Section 906 has been
provided to IBM and will be retained by IBM and furnished to the Securities and
Exchange Commission or its staff upon request.