Exhibit 99.5 AGREEMENT TO BE BOUND BY POWERTEL STOCKHOLDER AGREEMENT AND SIDE AGREEMENT The undersigned, TDSI Corporation, being the transferee from Telephone and Data Systems, Inc. ("TDS") of 35,570,493 shares of the common stock, par value $.001 per...Stockholder Agreement and Side Agreement • January 16th, 2001 • Telephone & Data Systems Inc Voting Trust 1989 • Delaware
The undersigned, TDSI Corporation, being the transferee from Telephone and Data Systems, Inc. ("TDS") of 35,570,493 shares of the common stock, par value $.001 per share, of VoiceStream Wireless Corporation, a Delaware corporation (the "Company"), as a condition to the receipt of such shares, acknowledges that matters pertaining to the voting, transfer and ownership of such shares is governed by the Stockholder Agreement dated as of August 26, 2000, between TDS and Powertel, Inc. and the Side Agreement dated as of August 26, 2000, between TDS and Powertel, Inc. (collectively, the "Agreements"), and hereby (1) acknowledges receipt of a copy of the Agreements, and (2) agrees to be bound, to the same extent as TDS has heretofore been bound, by the terms of the Agreements, as the same have been or may be amended from time to time.
