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                                                                     EXHIBIT 4.9
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                SECOND AMENDMENT TO SECOND SUPPLEMENTAL INDENTURE


                       INTERNATIONAL TRANSMISSION COMPANY


                                       TO


                    THE BANK OF NEW YORK TRUST COMPANY, N.A.


                                     Trustee


                              --------------------


                           Dated as of March 24, 2006


                              --------------------


               Supplementing the First Mortgage and Deed of Trust
                            Dated as of July 15, 2003

                   Amending the Second Supplemental Indenture
                     and the First Mortgage Bonds, Series B



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                                TABLE OF CONTENTS
                                                                            Page
                                                                            ----

ARTICLE ONE  DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION...........2


         Section 101.      Definitions.........................................2


ARTICLE TWO  AMENDMENTS........................................................2


         Section 201.      Amendments to the Second Supplemental Indenture.....2

         Section 202.      Amendment to the First Mortgage Bonds, Series B.....2


ARTICLE THREE   MISCELLANEOUS PROVISIONS.......................................2





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     SECOND AMENDMENT TO SECOND SUPPLEMENTAL INDENTURE, dated as of March 24,
2006, between International Transmission Company, a corporation organized and
existing under the laws of the State of Michigan (herein called the "COMPANY"),
having its principal office at 39500 Orchard Hill Place, Suite 200, Novi,
Michigan 48375 and THE BANK OF NEW YORK TRUST COMPANY, N.A. (as successor to BNY
MIDWEST TRUST COMPANY), a national banking association, as Trustee (herein
called the "TRUSTEE"), the office of the Trustee at which on the date hereof its
corporate trust business is principally administered being 2 N. LaSalle Street,
Suite 1020, Chicago, Illinois 60630.

                             RECITALS OF THE COMPANY

     WHEREAS, the Company has heretofore executed and delivered to the Trustee a
First Mortgage and Deed of Trust dated as of July 15, 2003 (the "ORIGINAL
INDENTURE") providing for the issuance by the Company from time to time of its
bonds, notes and other evidence of indebtedness to be issued in one or more
series (in the Original Indenture and herein called the "SECURITIES") and to
provide security for the payment of the principal of and premium, if any, and
interest, if any, on the Securities;

     WHEREAS, the Company has heretofore executed and delivered to the Trustee a
First Supplemental Indenture dated as of July 15, 2003 (the "FIRST SUPPLEMENTAL
INDENTURE") to the Original Indenture providing for the issuance by the Company
of $185,000,000 4.45% First Mortgage Bonds, Series A, due July 15, 2013;

     WHEREAS, the Company has heretofore executed and delivered to the Trustee a
Second Supplemental Indenture dated as of July 15, 2003 (the "SECOND
SUPPLEMENTAL INDENTURE") to the Original Indenture providing for the issuance by
the Company of First Mortgage Bonds, Series B, due February 28, 2006 (the "FIRST
MORTGAGE BONDS, SERIES B"), and an Amendment to Second Supplemental Indenture
dated as of January 19, 2005 (the Second Supplemental Indenture as so amended,
the "AMENDED SECOND SUPPLEMENTAL INDENTURE") providing for certain amendments to
the First Mortgage Bonds, Series B;

     WHEREAS, the Company, in the exercise of the power and authority conferred
upon and reserved to it under the provisions of the Original Indenture, as
amended and supplemented by the First Supplemental Indenture and the Amended
Second Supplemental Indenture (as so amended and supplemented, the "INDENTURE")
and pursuant to appropriate resolutions of the Board of Directors, has duly
determined to make, execute and deliver to the Trustee this Second Amendment to
Second Supplemental Indenture (the "SECOND AMENDMENT TO SECOND SUPPLEMENTAL
INDENTURE") in order to amend the Second Supplemental Indenture and the First
Mortgage Bonds, Series B as set forth in Article Two hereof; and

     WHEREAS, all things necessary to make this Second Amendment to Second
Supplemental Indenture a valid, binding and legal agreement of the Company, have
been done;

     NOW, THEREFORE, THIS SECOND AMENDMENT TO SECOND SUPPLEMENTAL INDENTURE
WITNESSETH that, in order to amend the terms of the First Mortgage Bonds, Series
B established in the Second Supplemental Indenture, it is mutually covenanted
and agreed as follows:





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                                   ARTICLE ONE

                        DEFINITIONS AND OTHER PROVISIONS
                             OF GENERAL APPLICATION

     Section 101. Definitions. Each capitalized term that is used herein and is
defined in the Original Indenture shall have the meaning specified in the
Original Indenture unless such term is otherwise defined herein.

                                   ARTICLE TWO

                                   AMENDMENTS

     Section 201. Amendments to the Second Supplemental Indenture. (a) Section
201 of the Second Supplemental Indenture shall be amended to read as follows:

     "Section 201. Title of the Series B Bonds. This Second Supplemental
     Indenture hereby creates a series of Securities designated as the "First
     Mortgage Bonds, Series B, due March 10, 2010" of the Company (the "SERIES B
     BONDS")."

          (b) Exhibit A of the Amended Second Supplemental Indenture is amended
by substituting "March 10, 2010" for each reference to "March 19, 2007."

     Section 202. Amendment to the First Mortgage Bonds, Series B. Each of the
First Mortgage Bonds, Series B heretofore issued and outstanding on the date
hereof shall be amended by substituting "March 10, 2010" for each reference
therein to "March 19, 2007."

                                  ARTICLE THREE

                            MISCELLANEOUS PROVISIONS

     The Trustee makes no undertaking or representations in respect of, and
shall not be responsible in any manner whatsoever for and in respect of, the
validity or sufficiency of this Second Amendment to Second Supplemental
Indenture, the Series B Bonds or the proper authorization or the due execution
hereof by the company or for or in respect of the recitals and statements
contained herein, all of which recitals and statements are made solely by the
Company. The Trustee shall not be accountable for the use or the application by
the Company of the Series B Bonds or of the proceeds thereof.

     Except as expressly amended and supplemented hereby, the Indenture shall
continue in full force and effect in accordance with the provisions thereof and
the Indenture is in all respects hereby ratified and confirmed. This Second
Amendment to Second Supplemental Indenture and all of its provisions shall be
deemed a part of the Indenture in the manner and to the extent herein and
therein provided.

     This Second Amendment to Second Supplemental Indenture and the Series B
Bonds shall be governed by and construed in accordance with the law of the State
of New York; except that (i) if this Second Amendment to Second Supplemental
Indenture shall become qualified and shall become subject to the Trust Indenture
Act, this Second Amendment to Second Supplemental Indenture and the Series B


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Bonds shall be governed by the Trust Indenture Act to the extent that the Trust
Indenture Act shall be applicable and (ii) if the law of any jurisdiction
wherein any portion of the Mortgaged Property is located shall mandatorily
govern the creation of a mortgage lien on and security interest in, or
perfection, priority or enforcement of the Lien of the Indenture or exercise of
remedies with respect to, such portion of the Mortgaged Property, this Second
Amendment to Second Supplemental Indenture and the Series B Bonds shall be
governed by the law of such jurisdiction to the extent mandatory.

     This Second Amendment to Second 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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     IN WITNESS WHEREOF, the parties hereto have caused this Second Amendment to
Second Supplemental Indenture to be duly executed as of the day and year first
above written.

                                      INTERNATIONAL TRANSMISSION
                                      COMPANY


                                      By: /s/ Daniel J. Oginsky
                                         ---------------------------------------
                                         Name:  Daniel J. Oginsky
                                         Title: Vice President and
                                                General Counsel

                                      THE BANK OF NEW YORK TRUST  COMPANY, N.A.,
                                      as Trustee

                                      By: /s/ Roxane Ellwanger
                                         ---------------------------------------
                                         Name:  Roxane Ellwanger
                                         Title: Assistant Vice President




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