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. Date: September 10, 2004 SMITH BARNEY FUND MANAGEMENT LLC By: /s/ Thomas C. Mandia -------------------------------------------- Name: Thomas C. Mandia Title: Secretary CITIGROUP GLOBAL MARKETS HOLDINGS INC. By: /s/ Serena D. Moe -------------------------------------------- Name: Serena D. Moe Title: Assistant Secretary CITIGROUP INC. By: /s/ Serena D. Moe -------------------------------------------- Name: Serena D. Moe Title: Assistant Secretary