Exhibit 32.1

   Certification Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002


In connection with this Amendment No. 1 on Form 10-K/A of Engineered Support
Systems, Inc. (the "Company") for the year ended October 31, 2004 (the
"Report"), I, Gerald A. Potthoff, Vice Chairman, Chief Executive Officer and
President of the Company, certify, pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002 that:

(1)      The Report complies with Sections 13(a) and 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.

Date: February 1, 2005



/s/ Gerald A. Potthoff
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Gerald A. Potthoff
Vice Chairman, Chief Executive Officer and President