Exhibit 99.1
                                                                    ------------

                             JOINT FILING AGREEMENT

         The undersigned hereby agree that the foregoing statement on Schedule
13G is, and any amendment thereto signed by each of the undersigned shall be,
filed on behalf of each undersigned pursuant to and in accordance with the
provisions of 13d-1(k) under the Securities Exchange Act of 1934 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 agreements. 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 it contained therein, but shall not be responsible
for the completeness and accuracy of the information concerning the other,
except to the extent that it knows or has reason to believe that such
information is inaccurate.

Dated: December 7, 2007

  STANDARD GENERAL L.P.


By:   /s/ Scott Cohen
      ----------------------------
      Name:    Scott Cohen
      Title:   Attorney-in-Fact

STANDARD GENERAL FUND L.P.


By:   /s/ Scott Cohen
      ----------------------------
      Name:    Scott Cohen
      Title:   Attorney-in-Fact

SOOHYUNG KIM


By:   /s/ Scott Cohen
      ----------------------------
      Name:    Scott Cohen
      Title:   Attorney-in-Fact

NICHOLAS J. SINGER


By:   /s/ Scott Cohen
      ----------------------------
      Name:    Scott Cohen
      Title:   Attorney-in-Fact