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Exhibit 31

Rule 13a-14(a)/15(d)-14(a) Certifications

        I, Paul D. Carrico, certify that:


Date: May 8, 2008   /s/  PAUL D. CARRICO      
Paul D. Carrico
President and Chief Executive Officer

I, Gregory C. Thompson, certify that:


Date: May 8, 2008   /s/  GREGORY C. THOMPSON      
Gregory C. Thompson
Treasurer and Chief Financial Officer



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CERTIFICATIONS
Rule 13a-14(a)/15(d)-14(a) Certifications