CUSIP No. 74060C105                  SCHEDULE 13G                  Page  9 of 9
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              JOINT FILING AGREEMENT PURSUANT TO RULE 13d-1(k)(1)

            The undersigned  acknowledge and agree that the foregoing statement
on  Schedule  13G is filed on  behalf of each of the  undersigned  and that all
subsequent  amendments  to this  statement  on  Schedule  13G shall be filed on
behalf of each of the  undersigned  without the necessity of filing  additional
joint  filing  statements.  The  undersigned  acknowledge  that  each  shall be
responsible for the timely filing of such amendments,  and for the completeness
and accuracy of the information concerning him, her or it contained herein, but
shall not be responsible for the  completeness  and accuracy of the information
concerning the other entities or persons,  except to the extent that he, she or
it knows or has reason to believe that such information is inaccurate.

Dated as of February 14, 2006


                                        CONTIGROUP COMPANIES, INC.



                                        By: /s/ Paul J. Fribourg
                                            --------------------------------
                                            Name:  Paul J. Fribourg
                                            Title: Chief Executive Officer



                                        /s/ Paul J. Fribourg
                                        ------------------------------------
                                        Paul J. Fribourg