EXHIBIT 1 --------- AGREEMENT AS TO JOINT FILING OF SCHEDULE 13G -------------------------------------------- Each of the undersigned hereby affirms that it is individually eligible to use Schedule 13G, and agrees that this Schedule 13G is filed on...

                                    EXHIBIT 1
                                    ---------

                  AGREEMENT AS TO JOINT FILING OF SCHEDULE 13G
                  --------------------------------------------

Each of the undersigned hereby affirms that it is individually eligible to use
Schedule 13G, and agrees that this Schedule 13G is filed on its behalf.

Dated: February 12, 2007


                                  CITIGROUP TRUST-DELAWARE, N.A.

                                  By: /s/ Xxxxx Xxxxx
                                  --------------------------------------------
                                  Name:   Xxxxx Xxxxx
                                  Title:  Chief Investment Officer


                                  CITIBANK, N.A.

                                  By: /s/ Xxx X. Xxxxxxx
                                  --------------------------------------------
                                  Name:   Xxx X. Xxxxxxx
                                  Title:  Assistant Secretary


                                  CITICORP HOLDINGS INC.

                                  By: /s/ Xxx X. Xxxxxxx
                                  --------------------------------------------
                                  Name:   Xxx X. Xxxxxxx
                                  Title:  Assistant Secretary


                                  CITIGROUP INC.

                                  By: /s/ Riqueza X. Xxxxxxx
                                  --------------------------------------------
                                  Name:   Riqueza X. Xxxxxxx
                                  Title:  Assistant Secretary