EXHIBIT 1

                            JOINT FILING UNDERTAKING

The undersigned, being duly authorized thereunto, hereby execute this agreement
as an exhibit to this Schedule 13D to evidence the agreement of the below-named
parties, in accordance with the rules promulgated pursuant to the Securities
Exchange Act of 1934, to file this Schedule jointly on behalf of each such
party.

Dated as of November 30, 2005

                         PARKCENTRAL GLOBAL HUB LIMITED




By:  /s/ DAVID RADUNSKY
     ---------------------
     Name:  David Radunsky
     Title: Chief Operating Officer
            Parkcentral Capital Management, L.P.
            Advisor to Parkcentral Global Hub Limited


PETRUS SECURITIES, LP



By:  /s/ DAVID RADUNSKY
     -------------------------
     Name:  David Radunsky
     Title: Chief Operating Officer