Exhibit 4
JOINT FILING AGREEMENT
PURSUANT TO RULE 13d-1(f)(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 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 others, except to the extent that it knows or has reason to believe that
such information is inaccurate. This Agreement may be executed in any number of
counterparts and all of such counterparts taken together shall constitute one
and the same instrument.
Dated: October 31, 1997
XXXXXXX, XXXXXX INVESTORS, L.P.
By: Warburg, Xxxxxx & Co., General Partner
By: /s/ Xxxxxxx Xxxxxxx
Partner
WARBURG, XXXXXX CAPITAL PARTNERS, L.P.
By: Warburg, Xxxxxx & Co., General Partner
By: /s/ Xxxxxxx Xxxxxxx
Partner
WARBURG, XXXXXX & CO.
By: /s/ Xxxxxxx Xxxxxxx
Partner
X.X. XXXXXXX, XXXXXX & CO., LLC
By: /s/ Xxxxxxx Xxxxxxx
Member
WARBURG, XXXXXX CAPITAL PARTNERS LIQUIDATING TRUST
By: /s/ Xxxxxxx Xxxxxxx
Trustee
