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EXHIBIT 99.1

SCHEDULE 13D JOINT FILING AGREEMENT

The undersigned and each other person executing this joint filing agreement (this "Agreement") agree as follows:

The undersigned and each other person executing this Agreement are responsible for the timely filing of such Schedule 13D and any amendments thereto, and for the completeness and accuracy of the information concerning such person contained therein; but none of the undersigned or any other person executing this Agreement is responsible for the completeness or accuracy of the information statement concerning any other persons making the filing, unless such person knows or has reason to believe that such information is inaccurate.

This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all of which, taken together, shall constitute one and the same instrument.

* * * * * *

IN WITNESS WHEREOF, the undersigned have caused this Agreement to be signed by their respective officers thereunto duly authorized as of the date set forth opposite their name.

Date: November 18, 2002

	XXI Merger Corp.
	By:	/s/ ORLANDO BRAVO
	Name:	Orlando Bravo
	Its:	President
	Thoma Cressey Fund VII, L.P.
	By:	TC Partners VII, L.P.
	Its:	General Partner
	By:	Thoma Cressey Equity Partners Inc.
	Its:	General Partner
	By:	/s/ LEE M. MITCHELL
	Name:	Lee M. Mitchell
	Its:	Secretary
	TC Partners VII, L.P.
	By:	Thoma Cressey Equity Partners Inc.
	Its:	General Partner
	By:	/s/ LEE M. MITCHELL
	Name:	Lee M. Mitchell
	Its:	Secretary
	Thoma Cressey Equity Partners Inc.
	By:	/s/ LEE M. MITCHELL
	Name:	Lee M. Mitchell
	Its:	Secretary

Page 18 of 26 Pages

	LLR Equity Partners, L.P.
	By:	LLR Capital, L.P.
	Its:	General Partner
	By:	LLR Capital LLC
	Its:	General Partner
	By:	/s/ MITCHELL L. HOLLIN
	Name:	Mitchell L. Hollin
	Its:	Managing Director
	LLR Equity Partners Parallel, L.P.
	By:	LLR Capital, L.P.
	Its:	General Partner
	By:	LLR Capital LLC
	Its:	General Partner
	By:	/s/ MITCHELL L. HOLLIN
	Name:	Mitchell L. Hollin
	Its:	Managing Director
	LLR Capital, L.P.
	By:	LLR Capital LLC
	Its:	General Partner
	By:	/s/ MITCHELL L. HOLLIN
	Name:	Mitchell L. Hollin
	Its:	Managing Director
	LLR Capital LLC
	By:	/s/ MITCHELL L. HOLLIN
	Name:	Mitchell L. Hollin
	Its:	Managing Director

Page 19 of 26 Pages

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EXHIBIT 99.1

SCHEDULE 13D JOINT FILING AGREEMENT

PROPHET 21 INC SC 13D