Exhibit 4
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JOINT FILING AGREEMENT
The undersigned hereby agree that Amendment No. 3 to Schedule 13D under the
Securities and Exchange Act of 1934, as amended, relating to shares of the
common stock, par value $0.01 per share of Xpedior Incorporated, to which this
Agreement is an Exhibit and which is to be filed with the Securities and
Exchange Commission, is filed on behalf of each of the undersigned.
This Agreement may be executed in several counterparts, each of which shall
be an original but all of which together shall constitute one and the same
instrument.
Dated as of November 1, 2000
PSINet INC.
By: /s/ Kathleen B. Horne
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Name: Kathleen B. Horne
Title: Senior Vice President
PSINet CONSULTING SOLUTIONS HOLDINGS, INC.
By: /s/ Edward L. Pierce
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Name: Edward L. Pierce
Title: Executive Vice President
