Deltek (PROJ) 10-Q 2008 Q1 Quarterly report

Exhibit 32.1

Certification of Chief Executive Officer and Chief Financial Officer

Pursuant to 18 U.S.C. Section 1350,

as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

I, Kevin T. Parker, certify pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly Report of Deltek, Inc. on Form 10-Q for the quarterly period ended March 31, 2008 fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and the information contained in such Form 10-Q fairly presents, in all material respects, the financial condition and results of operations of Deltek, Inc.

Date: May 15, 2008	/s/ Kevin T. Parker
	Kevin T. Parker
	Chairman, President and Chief Executive Officer
	(Principal Executive Officer)

I, James C. Reagan, certify pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly Report of Deltek, Inc. on Form 10-Q for the quarterly period ended March 31, 2008 fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and the information contained in such Form 10-Q fairly presents, in all material respects, the financial condition and results of operations of Deltek, Inc.

Date: May 15, 2008	/s/ James C. Reagan
	James C. Reagan
	Executive Vice President, Chief Financial Officer and Treasurer
	(Principal Financial and Accounting Officer)