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EXHIBIT 99.1
JOINT FILING AGREEMENT
We, the signatories of the statement to which this Joint Filing
Agreement is attached, hereby agree that such statement is filed, and any
amendments thereto filed by either or both of us will be filed, on behalf of
each of us.
Dated: August 17, 2000.
VULCAN VENTURES INCORPORATED
By: /s/ WILLIAM D. SAVOY
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William D. Savoy, Vice President
/s/ PAUL G. ALLEN
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Paul G. Allen
*By: /s/ WILLIAM D. SAVOY
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William D. Savoy as Attorney-in Fact for Paul
G. Allen pursuant to a Power of Attorney
filed on August 30, 1999, with the Schedule
13G of Vulcan Ventures Incorporated and Paul
G. Allen for Pathogenesis, Inc. and
incorporated herein by reference.
