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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        As an independent registered public accounting firm, we hereby consent to the use of our report dated March 25, 2005 (and to all references to our firm) included in or made a part of this Registration Statement.

/s/ Hein & Associates LLP

Dallas, Texas
May 16, 2005

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CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM