Form: SC 13G

Schedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities by passive investors and certain institutions

February 8, 2007

EXHIBIT 99.1

Published on February 8, 2007




EXHIBIT 1
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AGREEMENT AS TO JOINT FILING OF SCHEDULE 13G
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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 9, 2007

CITIGROUP GLOBAL MARKETS INC.


By: /s/ Riqueza V. Feaster
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Name: Riqueza V. Feaster
Title: Assistant Secretary



CITIGROUP FINANCIAL PRODUCTS INC.


By: /s/ Riqueza V. Feaster
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Name: Riqueza V. Feaster
Title: Assistant Secretary



CITIGROUP GLOBAL MARKETS HOLDINGS INC.


By: /s/ Riqueza V. Feaster
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Name: Riqueza V. Feaster
Title: Assistant Secretary



CITIGROUP INC.


By: /s/ Riqueza V. Feaster
--------------------------------------------
Name: Riqueza V. Feaster
Title: Assistant Secretary