JOINT FILING AGREEMENT PURSUANT TO RULE 13D-1(K)(1)

EXHIBIT 1

JOINT FILING AGREEMENT

PURSUANT TO RULE 13D-1(K)(1)

The undersigned acknowledge and agree that the foregoing statement on Schedule 13D is filed on behalf of each of the undersigned and that all subsequent amendments to this statement on Schedule 13D shall be filed on behalf of each of the undersigned without the necessity of filing additional joint acquisition statements. 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 him or it contained therein, but shall not be responsible for the completeness and accuracy of the information concerning the others, except to the extent that it knows or has reason to believe that such information is inaccurate.

Dated: November 24, 2003				KKR–ZT, L.L.C. By: KKR 1996 FUND L.P., senior member By: KKR ASSOCIATES 1996, L.P., general partner By: KKR 1996 GP LLC, general partner
						/s/    XXXXXXX X. XXXXXXXXXX
				Name:		Xxxxxxx X. Xxxxxxxxxx
				Title:		Attorney-in-fact for Xxxxx X. Xxxxxx, Xx.
				KKR 1996 FUND L.P. By: KKR ASSOCIATES 1996, L.P., general partner By: KKR 1996 GP LLC, general partner
						/s/    XXXXXXX X. XXXXXXXXXX
				Name:		Xxxxxxx X. Xxxxxxxxxx
				Title:		Attorney-in-fact for Xxxxx X. Xxxxxx, Xx.
				KKR ASSOCIATES 1996, L.P. By: KKR 1996 GP LLC, general partner
						/s/    XXXXXXX X. XXXXXXXXXX
				Name:		Xxxxxxx X. Xxxxxxxxxx
				Title:		Attorney-in-fact for Xxxxx X. Xxxxxx, Xx.
				KKR 1996 GP LLC
						/s/    XXXXXXX X. XXXXXXXXXX
				Name:		Xxxxxxx X. Xxxxxxxxxx
				Title:		Attorney-in-fact for Xxxxx X. Xxxxxx, Xx.