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                                                                    Exhibit 10.5

                                                                  EXECUTION COPY

                  THIS FIRST SUPPLEMENTAL INDENTURE, dated as of December 31,
2003 (this "Supplemental Indenture"), is by and among Rogers Cable Inc.,
formerly known as Rogers Cablesystems Limited, a corporation organized under the
laws of the Province of Ontario (hereinafter called "Rogers Cable"), Rogers
Cable Communications Inc., a corporation organized under the laws of the
Province of Ontario and a wholly-owned subsidiary of Rogers Cable (hereinafter
called "RCCI"), Rogers Cablesystems Ontario Limited, a corporation organized
under the laws of the Province of Ontario (hereinafter called "Rogers Ontario"),
Rogers Ottawa Limited/Limitee, a corporation organized under the laws of the
Province of Ontario (hereinafter called "Rogers Ottawa"), Rogers Cablesystems
Georgian Bay Limited, a corporation organized under the laws of the Province of
Ontario (hereinafter called "Rogers Georgian Bay"), Rogers Cable Atlantic Inc.,
a corporation organized under the laws of the Province of Ontario (hereinafter
called "Rogers Atlantic"), 1443358 Ontario Inc., a corporation organized under
the laws of the Province of Ontario (hereinafter called "1443358 Ontario" and,
together with RCCI, Rogers Ontario, Rogers Ottawa, Rogers Georgian Bay and
Rogers Atlantic, the "Guarantors") and JPMorgan Chase Bank, formerly known as
Chemical Bank, a New York banking corporation, as trustee (hereinafter called
the "Trustee").

                               W I T N E S S E T H

                  WHEREAS, Rogers Cable and the Trustee, as well as Rogers
Ontario, Rogers Ottawa and Rogers Georgian Bay, are parties to an indenture
dated as of November 30, 1995 (the "Indenture"), pursuant to which Rogers
Cable's outstanding 11% Senior Subordinated Guaranteed Debentures due December
1, 2015 (the "Debentures") are issued, which Debentures constitute "Securities"
as that term is defined in the Indenture;

                  WHEREAS, in accordance with the terms of the Indenture, Rogers
Atlantic became a Guarantor on March 28, 2001, and RCCI and 1443358 Ontario each
became a Guarantor on December 17, 2003;

                  WHEREAS, in connection with a corporate restructuring, Rogers
Cable intends to transfer certain of its properties, assets and liabilities
constituting its assets substantially as an entirety to RCCI (the "Transfer");

                  WHEREAS, pursuant to Section 801(a) of the Indenture, in
connection with the Transfer, RCCI is required to execute and deliver to the
Trustee a supplemental indenture assuming all of the obligations under the
Securities and the Indenture;

                  WHEREAS, Section 802 of the Indenture provides that upon the
transfer of the properties and assets of the Company substantially as an
entirety in accordance with Section 801 of the Indenture, (i) the successor
Person shall succeed to, and be substituted for, and may exercise every right
and power of, the Company under the Indenture with the same effect as if such
successor Person had been named as the Company in the Indenture and (ii) except
in the case of a lease, the Company shall be discharged from all obligations and
covenants under the Indenture and the Securities;

                  WHEREAS, Rogers Cable, RCCI and the Trustee desire that,
following the Transfer, (i) Rogers Cable shall not be discharged from its
obligations and covenants under the

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Indenture and the Securities, but shall continue as the Company for all purposes
of the Indenture and the Securities; (ii) RCCI shall assume, as a co-obligor on
a joint and several basis with Rogers Cable, all of the Company's obligations
under the Securities and the Indenture; and (iii) to the extent provided herein
each of Rogers Cable and RCCI shall be the Company for purposes of the Indenture
as if each of them had been named as the Company therein;

                  WHEREAS, Section 901 of the Indenture provides that without
the consent of any Holders, the Company and the Guarantors, each when authorized
by a Board Resolution, and the Trustee, at any time and from time to time, may
enter into one or more indentures supplemental to the Indenture, to, among other
things, evidence the assumption by any successor Person of the covenants of the
Company in the Indenture and in the Securities, as the case may be, or, to make
any other change that does not adversely affect the rights of any Holder; and

                  WHEREAS, Rogers Cable, each of the Guarantors and RCCI have
complied with all conditions precedent provided for in the Indenture relating to
this Supplemental Indenture.

                  NOW, THEREFORE, for and in consideration of the foregoing
premises, Rogers Cable, RCCI, the Guarantors and the Trustee hereby agree for
the equal and ratable benefit of the Holders as follows:

                  1. Capitalized Terms. Capitalized terms used herein without
definition shall have the meanings assigned to them in the Indenture.

                  2. Assumption by RCCI. RCCI hereby assumes, as a co-obligor on
a joint and several basis with Rogers Cable, all obligations and covenants of
the Company under the Indenture and the Securities, including without limitation
obligations for the due and punctual payment of the principal of, premium, if
any, and interest on all Securities issued or to be issued pursuant to the
Indenture and the performance or observance of each other obligation and
covenant set forth in the Indenture to be performed or observed on the part of
the Company.

                  3. Rogers Cable not Discharged. Notwithstanding Section 802 of
the Indenture, following the Transfer, Rogers Cable shall not be discharged from
its obligations and covenants under the Indenture and the Securities.

                  4. References to the "Company" in the Indenture. Following the
Transfer, all references to the "Company" in the Indenture shall be deemed to be
references to each of Rogers Cable and RCCI, as co-obligors on a joint and
several basis; provided, that (i) with respect to any matter to be determined on
a Consolidated basis for the Company and its Restricted Subsidiaries, such
matter shall be determined for Rogers Cable and its Restricted Subsidiaries,
treating RCCI for such purposes as a Restricted Subsidiary; (ii) where the
context requires that a reference to the "Company" refer to a single entity
only, such reference shall be deemed to be to Rogers Cable only; and (iii) all
references to the board of directors or any officer of the "Company" shall be
deemed to be references to the board of directors or such officer of Rogers
Cable.

                  5. Notices. (a) Section 106(b) of the Indenture is hereby
amended and restated in its entirety as follows:

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                           (b) Rogers Cable Inc. or Rogers Cable Communications
                  Inc. by the Trustee or any Holder shall be sufficient for
                  every purpose hereunder (unless otherwise herein expressly
                  provided) if made, given, furnished or delivered in writing to
                  Rogers Cable Inc. or Rogers Cable Communications Inc., as the
                  case may be, to 333 Bloor Street East, 10th Floor, Toronto,
                  Ontario, Canada, M4W 1G9, Attention: Vice-President,
                  Treasurer, fax: 416-935-3598, with a copy to the
                  Vice-President, General Counsel and Secretary, fax:
                  416-935-3548, or, in either case, at any other address
                  previously furnished in writing to the Trustee by Rogers Cable
                  Inc. or Rogers Cable Communications Inc.

         (b) At the date of execution of this Supplemental Indenture, the
Corporate Trust Office is located at 4 New York Plaza, 15th Floor, New York, New
York 10004, Attention: Institutional Trust Services.

                  6. Trustee's Acceptance. The Trustee hereby accepts this
Supplemental Indenture and agrees to perform the same under the terms and
conditions set forth in the Indenture.

                  7. Guarantors' Acceptance. Each of the Guarantors hereby
accepts this Supplemental Indenture and agrees to perform the same under the
terms and conditions set forth in the Indenture.

                  8. Responsibility of Trustee. The recitals contained herein
shall be taken as the statements of Rogers Cable, RCCI and the Guarantors, and
the Trustee assumes no responsibility for the correctness of such recitals. The
Trustee makes no representation as to the validity or sufficiency of this
Supplemental Indenture.

                  9. Effect of Supplemental Indenture. Upon the execution and
delivery of this Supplemental Indenture by Rogers Cable, RCCI, each of the
Guarantors and the Trustee, the Indenture shall be supplemented and amended in
accordance herewith, and this Supplemental Indenture shall form a part of the
Indenture for all purposes, and every Holder of a Security heretofore or
hereafter authenticated and delivered under the Indenture shall be bound
thereby.

                  10. Indenture Remains in Full Force and Effect. Except as
supplemented or amended hereby, all other provisions in the Indenture and the
Securities, to the extent not inconsistent with the terms and provisions of this
Supplemental Indenture, shall remain in full force and effect.

                  11. Incorporation of Indenture. All the provisions of this
Supplemental Indenture shall be deemed to be incorporated in, and made a part
of, the Indenture; and the Indenture, as supplemented and amended by this
Supplemental Indenture, shall be read, taken and construed as one and the same
instrument.

                  12. Counterparts. This Supplemental Indenture may be executed
in any number of counterparts, each of which so executed shall be deemed to be
an original, but all such counterparts shall together constitute but one and the
same instrument.

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                  13. Effect of Headings. The headings of this Supplemental
Indenture are inserted for convenience of reference and shall not be deemed to
be a part thereof.

                  14. Conflict with Trust Indenture Act. If any provision of
this Supplemental Indenture limits, qualifies or conflicts with any provision of
the Trust Indenture Act that is required under the Trust Indenture Act to be
part of and govern any provision of this Supplemental Indenture, the provision
of the Trust Indenture Act shall control. If any provision of this Supplemental
Indenture modifies or excludes any provision of the Trust Indenture Act that may
be so modified or excluded, the provision of the Trust Indenture Act shall be
deemed to apply to the Indenture as so modified or to be excluded by this
Supplemental Indenture, as the case may be.

                  15. Successors. All covenants and agreements in this
Supplemental Indenture by RCCI, the Guarantors and Rogers Cable shall be binding
upon and accrue to the benefit of their respective successors. All covenants and
agreements in this Supplemental Indenture by the Trustee shall be binding upon
and accrue to the benefit of its successors.

                  16. Benefits of Supplemental Indenture. Nothing in this
Supplemental Indenture, the Indenture or the Securities, express or implied,
shall give to any Person, other than the parties hereto and thereto and their
successors hereunder and thereunder and the Holders, any benefit of any legal or
equitable right, remedy or claim under this Supplemental Indenture, the
Indenture or the Securities.

                  17. GOVERNING LAW. THE LAWS OF THE STATE OF NEW YORK, WITHOUT
REGARD TO PRINCIPLES OF CONFLICTS OF LAW, SHALL GOVERN THIS SUPPLEMENTAL
INDENTURE.

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                  IN WITNESS WHEREOF, the parties hereto have caused this
Supplemental Indenture to be duly executed, all as of the date first above
written.

                                    ROGERS CABLE INC.,

                                    By:    /s/ M.L. Daly
                                           ------------------------------------
                                           Name:
                                           Title:

                                    By:    /s/ Alan Horn
                                           ------------------------------------
                                           Name:
                                           Title:

                                    ROGERS CABLE COMMUNICATIONS INC.,

                                    By:    /s/ M.L. Daly
                                           ------------------------------------
                                           Name:
                                           Title:

                                    By:    /s/ Alan Horn
                                           ------------------------------------
                                           Name:
                                           Title:

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                                    ROGERS CABLESYSTEMS ONTARIO LIMITED,

                                    By:    /s/ M.L. Daly
                                           ------------------------------------
                                           Name:
                                           Title:

                                    By:    /s/ Alan Horn
                                           ------------------------------------
                                           Name:
                                           Title:

                                    ROGERS OTTAWA LIMITED/LIMITEE,

                                    By:    /s/ M.L. Daly
                                           ------------------------------------
                                           Name:
                                           Title:

                                    By:    /s/ Alan Horn
                                           ------------------------------------
                                           Name:
                                           Title:

                                    ROGERS CABLESYSTEMS GEORGIAN BAY LIMITED,

                                    By:    /s/ M.L. Daly
                                           ------------------------------------
                                           Name:
                                           Title:

                                    By:    /s/ Alan Horn
                                           ------------------------------------
                                           Name:
                                           Title:


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                                    ROGERS CABLE ATLANTIC INC.,

                                    By:    /s/ M.L. Daly
                                           ------------------------------------
                                           Name:
                                           Title:

                                    By:    /s/ Alan Horn
                                           ------------------------------------
                                           Name:
                                           Title:

                                    1443358 ONTARIO INC.,


                                    By:    /s/ M.L. Daly
                                           ------------------------------------
                                           Name:
                                           Title:

                                    By:    /s/ Alan Horn
                                           ------------------------------------
                                           Name:
                                           Title:

                                    JPMORGAN CHASE BANK,
                                    as Trustee,

                                    By:    /s/ Rosa Ciaccia
                                           ------------------------------------
                                           Name:  Rosa Ciaccia
                                           Title: Trust Officer

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