Exhibit 32.02

CERTIFICATION OF PRINCIPAL FINANCIAL OFFICER 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 ACI Worldwide, Inc. (the “Company”) on Form 10-Q for the quarter ended March 31, 2008 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Scott W. Behrens, Principal Financial Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

1)The Report fully complies with the requirements of Sections 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.

Date: May 9, 2008	/s/ SCOTT W. BEHRENS
	Scott W. Behrens
	Vice President, Corporate Controller and Chief Accounting Officer (Principal Financial Officer)

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