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                                                                    Exhibit 24.2


                                POWER OF ATTORNEY

        The person whose signature appears below hereby constitutes and appoints
David M. Kavanagh, Wesley G. Nissen and Mark D. Wood her true and lawful
attorneys-in-fact and agents, acting alone, with full power of substitution and
resubstitution, to sign on her behalf, individually and in each capacity stated
below, all amendments and post-effective amendments to this Registration
Statement on Form S-1 (including any registration statement filed pursuant to
Rule 462(b), (c) or (d) under the Securities Act of 1933, and all amendments
thereto) and to file the same, with all exhibits thereto and any other documents
in connection therewith, with the Securities and Exchange Commission under the
Securities Act of 1933, granting unto said attorneys-in-fact and agents 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 and to all intents and
purposes as each might or could do in person, hereby ratifying and confirming
each act that said attorneys-in-fact and agents may lawfully do or cause to be
done by virtue thereof.

        Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed below by the following person, in her
capacity as chief financial officer of Dearborn Capital Management, L.L.C., the
general partner of the registrant, on June 12, 2003.

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                     SIGNATURE                                            TITLE
                     ---------                                            -----
                                                    

                /s/ Maureen O'Rourke                    CHIEF FINANCIAL OFFICER
           -------------------------------------        (PRINCIPAL FINANCIAL AND ACCOUNTING OFFICER)
                  Maureen O'Rourke
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