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Exhibit 24.2

POWER OF ATTORNEY

        KNOW ALL PERSONS BY THESE PRESENTS, that the person whose signature appears below constitutes and appoints Roger L. Hawley and David W. Nassif, and each of them, his true and lawful attorneys-in-fact and agents, each with full power of substitution and resubstitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to the Registration Statement on Form S-1 (SEC File No. 333-149846), and to sign any registration statement for the same offering covered by such Registration Statement that is to be effective upon filing pursuant to Rule 462(b) promulgated under the Securities Act of 1933, as amended, and all post-effective amendments thereto, and to file the same, with all exhibits thereto and all documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that such attorneys-in-fact and agents or any of them, or his or their substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Signature	Title	Date
/s/ Erle T. Mast
	Director	June 18, 2008
Erle T. Mast

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Exhibit 24.2

POWER OF ATTORNEY