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                                                                   EXHIBIT 10.29

                                CoreComm Limited
                              CoreComm Holdco, Inc.
                              110 East 59th Street
                               New York, NY 10022

                                                                February 5, 2002

NTL incorporated
110 E. 59th Street
New York, New York 10022
Attention: Richard J. Lubasch

Mr. Lubasch:

         This letter agreement is to confirm that the parties agree that
as of the date hereof, with respect to the 10.75% Unsecured Convertible PIK
Notes due 2011, dated October 15, 2001, and any additional 10.75% Unsecured
Convertible PIK Notes (collectively, the "Notes"), issued, or to be issued,
respectively, CoreComm Limited and/or CoreComm Holdco, Inc. ("Holdco") as
obligors in favor of NTL Incorporated ("NTL");

         CoreComm Limited and CoreComm Holdco hereby exercise their right under
         Section (9) of the Notes such that, following the completion of
         Holdco's exchange offer to the holders of CoreComm Limited common stock
         to exchange their shares of CoreComm Limited common stock for shares of
         Holdco common stock, the convertibility feature of the Notes will be
         altered so that rather than the Notes being convertible into shares of
         CoreComm Limited common stock, they will become convertible into shares
         of Holdco common stock. At that time, the conversion prices of each
         Note will be equitably adjusted by dividing the conversion price then
         in effect by the exchange ratio at the completion of the exchange offer
         for CoreComm Limited common stock (for example, an initial exchange
         ratio of 1/38.9 and a conversion price of $1.00 would result in a new
         conversion price of $38.90 for each share of CoreComm Holdco common
         stock, as may be adjusted from time to time as set forth in the Notes),
         as may thereafter be adjusted pursuant to the Notes. NTL hereby agrees
         not to exercise its rights to convert the Notes into CoreComm Limited
         common stock until August 5, 2002 (unless that right has previously
         ceased as a result of the completion of the exchange offer and the
         change in the convertibility feature). In the event that Holdco does
         not complete the exchange offer for CoreComm Limited common stock by
         August 5, 2002, the conversion feature of the Notes will remain into
         CoreComm Limited common stock on its original terms. This letter
         agreement is to be governed by the laws of the State of New York.

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NTL Incorporated
February 5, 2002
Page 2

         Please indicate your agreement with the foregoing by signing below.

                                           Sincerely,

                                           CORECOMM LIMITED

                                           By: /s/ Michael A. Peterson
                                               ---------------------------------
                                               Name:  Michael A. Peterson
                                               Title: Executive Vice President

                                           CORECOMM HOLDCO, INC.

                                           By: _________________________________
                                               Name:  Thomas J. Gravina
                                               Title: Chief Executive Officer

Accepted and Agreed:

NTL INCORPORATED

By: ________________________________
    Name:  Richard J. Lubasch
    Title: Executive Vice President