Exhibit A

JOINT FILING STATEMENT

     The undersigned hereby agree that the Statement on Schedule 13G filed herewith (and any amendments thereto), is being filed jointly with the Securities and Exchange Commission pursuant to Rule 13d-1(k) (1) under the Securities Exchange Act of 1934, as amended, on behalf of each such person.

Dated: December 12, 2006

CROSSROADS 1999 SERIES DIRECT CO-INVESTMENT PORTFOLIO A, L.P.
By:	Crossroads Corporate Investors II, L.P.
	the general partner

By:	Crossroads Corporate Investors II GP, L.L.C.,
	the general partner

By:	/s/ Brad K. Heppner
	Brad K. Heppner, Manager

CROSSROADS CORPORATE INVESTORS II, L.P.
By:	Crossroads Corporate Investors II GP, L.L.C.,
	the general partner

By:	/s/ Brad K. Heppner
	Brad K. Heppner, Manager

CROSSROADS CORPORATE INVESTORS II GP, L.L.C.
By:	/s/ Brad K. Heppner
	Brad K. Heppner, Manager

LEHMAN BROTHERS HOLDINGS INC
By:	/s/ Barrett S. DiPaolo
	Barrett S. DiPaolo, Vice President

LEHMAN BROTHERS PRIVATE FUNDS INVESTMENT COMPANY GP, LLC
By:	/s/ Scott Christiansen
	Scott Christiansen, Vice President
BRADLEY K. HEPPNER
/s/ Bradley K. Heppner
Bradley K. Heppner
CROSSROADS CORNERSTONE DIRECT/CO-INVESTMENT FUND V, L.P.
By:	Lehman Crossroads Corporate Investors, LP the general partner

By: Lehman Crossroads Corporate Investors
GP, LLC, the general partner

By:	/s/ Scott Christiansen
	Scott Christiansen, Vice President

CROSSROADS CORPORATE INVESTORS, L.P.
By:	Lehman Crossroads Corporate Investors GP, LLC,
	the general partner

By:	/s/ Scott Christiansen
	Scott Christiansen, Vice President

CROSSROADS CORPORATE INVESTORS GP, LLC
By:	/s/ Scott Christiansen
	Scott Christiansen, Vice President