Form: SC 13G/A

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 4, 2003

JOINT FILING AGREEMENT

Published on February 4, 2003

EXHIBIT 1

JOINT FILING AGREEMENT

The undersigned hereby agree to the joint filing of the Schedule 13G to
which this Agreement is attached.

Dated: February 4, 2003

WAM Acquisition GP, Inc.
for itself and as general partner of
LIBERTY WANGER ASSET MANAGEMENT, L.P.

By: /s/ Bruce H. Lauer
----------------------------------------
Bruce H. Lauer
Senior Vice President and Secretary

LIBERTY ACORN TRUST

By: /s/ Bruce H. Lauer
----------------------------------------
Bruce H. Lauer
Vice President, Treasurer and
Secretary

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