Exhibit 2.3






                                                      Execution Version



                          DATED AS OF JANUARY 17, 2007


                                     BETWEEN

                           GATX FINANCIAL CORPORATION
                                    as Seller

                                       and

                       MACQUARIE AIRCRAFT LEASING LIMITED
                                    as Buyer

                        RELATING TO THE SALE AND PURCHASE

                                       of

                              THE GATX AIR BUSINESS

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

                          SECOND SUPPLEMENTAL AGREEMENT

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









SECOND SUPPLEMENTAL AGREEMENT dated as of January 17, 2007 between GATX
Financial Corporation, a Delaware corporation ("SELLER"), and Macquarie Aircraft
Leasing Limited, a company incorporated under the laws of the Republic of
Ireland ("BUYER").

WITNESSETH:

WHEREAS, Seller and Buyer entered into the Sale and Purchase Agreement.

WHEREAS, Seller and Buyer entered into the First Supplemental Agreement amending
the Sale and Purchase Agreement and agreeing certain additional matters.

WHEREAS, Seller and Buyer wish to make certain further amendments to the Sale
and Purchase Agreement and supplement certain of the agreements set forth in the
Sale and Purchase Agreement.

Accordingly, for good and valuable consideration, the receipt and sufficiency of
which is hereby acknowledged, Seller and Buyer agree as follows:


1.        DEFINITIONS

1.1       Definitions

          As used in this Second Supplemental Agreement (including the recitals
          hereto) and save as otherwise defined herein, terms defined in the
          Sale and Purchase Agreement shall bear the same respective meanings
          ascribed to them in the Sale and Purchase Agreement when used in this
          Second Supplemental Agreement and:

          "FIRST SUPPLEMENTAL AGREEMENT" means the Supplemental Agreement dated
          as of November 30, 2006 between Seller and Buyer amending and
          supplementing the Sale and Purchase Agreement.

          "SALE AND PURCHASE AGREEMENT" means the Sale and Purchase Agreement
          dated as of September 28, 2006 between Seller and Buyer.

1.2       Other Definitional and Interpretative Provisions

          Clause 1.2 of the Sale and Purchase Agreement is hereby deemed to be
          incorporated herein as if all references therein to "this Agreement"
          were references to this Second Supplemental Agreement.


2.        AMENDMENTS

          The Sale and Purchase Agreement is amended as follows:

2.1       The definition of the expressions ""KNOWLEDGE", "KNOWLEDGE" or any
          other similar knowledge qualification in this Agreement with respect
          to Seller" as set forth in Clause 1.1 is deleted and replaced with the
          following:

          ""KNOWLEDGE", "KNOWLEDGE" or any other similar knowledge qualification
          in this Agreement with respect to Seller means the actual knowledge of
          (i) (other than with respect to Clauses 3.9.3 or 3.9.9 (solely with
          respect to Manuals and Technical Records),


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          3.13 and 8.2) Jim Morris or Sue Noack, (ii) (solely with respect to
          Clauses 3.9.3 and 3.9.9 (but solely with respect to Manuals and
          Technical Records)) Phil Nassar, and (iii) (solely with respect to
          Clause 8.2) Jeff Young and Stanton Brunner provided that for all
          purposes of this Agreement none of the foregoing Persons shall be
          deemed to have actual knowledge of any matter of which any of such
          Persons obtained actual knowledge of on or after November 30, 2006 and
          of which any director or employee of Buyer or any Affiliate of Buyer
          has obtained the same actual knowledge on or after November 30, 2006
          as a consequence of, or in connection with, Buyer providing the
          management services to which reference is made in Clauses 6.4 and 6.9
          or in relation to the EAST Management Agreement.".

2.2       The following definitions are inserted in alphabetical order in Clause
          1.1:

          "EAST MANAGEMENT AGREEMENT ASSIGNMENT AGREEMENT" means the assignment,
          assumption and amendment agreement relating to the East Management
          Agreement in the agreed form.

          "EX-IM 2001 MANAGEMENT AGREEMENTS" means together the management
          agreements to which Seller is a party which constitute Virtual Data
          Room documents 11.49.31, 11.50.29 and 11.51.31 (each an "EX-IM 2001
          MANAGEMENT AGREEMENT").", and

          ""MANAGEMENT AGREEMENT EVENT OF DEFAULT" has the meaning ascribed to
          such term in the Ex-Im 2001 Financing Documents.".

2.3       The following expressions are inserted as new additional final
          sentences in Clause 2.2:

          "Buyer shall use all commercially reasonable efforts to ensure that
          all ancillary documentation needed to be executed and delivered in
          connection with the transfer of the EAST Management Agreement to Buyer
          is so executed and delivered as soon as practicable. The Parties
          acknowledge that as from January 17, 2007 Clifford Chance LLP is
          holding in escrow execution pages of the East Management Agreement
          Assignment Agreement executed by Seller and Buyer respectively and
          that upon the delivery to Clifford Chance LLP of execution pages of
          the East Management Agreement Assignment Agreement executed by EAST,
          the transfer of the East Management Agreement from Seller to Buyer
          shall be unconditionally effective. In addition, the Parties hereto
          shall use all good faith efforts to complete the transfer of all of
          the Material Contracts and Designated Contracts to Buyer no later than
          March 31, 2007.".

2.4       The following expression is inserted in the final line of Clause 2.5
          immediately following the expression "any GATX Retained Entity":

          "and provided further that as between Seller and Buyer the provisions
          of Clause 2.5 shall apply notwithstanding that the stated terms of any
          relevant document transferring the relevant Liabilities to which
          reference is made therein may otherwise provide that the relevant GATX
          Retained Entity or Buyer may bear any other liability in favour of any
          other party and Seller and Buyer agree to bear such other liability in
          accordance with the provisions of Clause 2.5 and indemnify and hold
          harmless the relevant GATX Retained Entity or Buyer, as the case may
          be, in respect thereof.".


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2.5       The expression "and" which appears as the end of Clause 2.5.7 is
          deleted.

2.6       The punctuation mark "," which appears at the end of line 4 of Clause
          2.5.8 is deleted and replaced with the expression "; and".

2.7       The following provision is inserted as Clause 2.5.9:

          "2.5.9 notwithstanding anything to the contrary in this Agreement, all
          Liabilities in respect of any claim in damages made by any JV Member
          or other third party in relation to, or as a consequence of, the use
          of any particular form of document, or the terms thereof, which is, or
          are, agreed by Buyer to transfer any Specified Ownership Interest (or
          Material Contract or Designated Contract) transferred on any Deferred
          Date rather than any other form (or terms thereof) or the manner in
          which any Specified Ownership Interest (or Material Contract or
          Designated Contract) is transferred,".

2.8       The following expression is inserted at the end of the final line of
          Clause 2.5 immediately following the expression "GATX Retained
          Entity":

          "and for the avoidance of doubt it is confirmed that the Liabilities
          under each Designated Contract and each Material Contract specified in
          Clauses 2.5.2 and 2.5.3 shall, without any further action on the part
          of any Party, be Assumed Liabilities as of the Closing Date or the
          applicable Deferred Date, as the case may be, whether or not such
          Designated Contract or Material Contract is transferred to Buyer".

2.9       The following expression is inserted as an additional sentence
          commencing in the final line of Clause 2.10.2 immediately following
          the expression "by Seller.":

          "In the event that any cash distribution as aforesaid is received by
          Seller following the Deferred Date on which the related Remaining
          Ownership Interest is transferred to Buyer and receipt of the same had
          not been anticipated for the purposes of calculating the sum payable
          by Buyer in order to satisfy Buyer's obligation to pay the relevant
          Deferred Date Allocated Amount, Seller shall promptly pay to Buyer the
          amount equal to such cash distribution so received by Seller.".

2.10      The following expression is inserted as an additional sentence
          commencing in the final line of Clause 2.10.3 immediately following
          the expression "Assumed Liabilities.":

          "Buyer and Seller acknowledge that, notwithstanding anything to the
          contrary contained in this Agreement, neither Seller nor any other
          GATX Retained Entity will have any liability to Buyer and, save as set
          forth in Clause 2.5.9, Buyer will not have any liability to Seller or
          any other GATX Retained Entity, in relation to, or as a consequence
          of, the use of any particular form of document, or the terms thereof,
          which is, or are, agreed by Seller and Buyer to transfer any Specified
          Ownership Interest (or Material Contract or Designated Contract)
          transferred on any Deferred Date rather than any other form (or terms
          thereof) or the manner in which any Specified Ownership Interest (or
          Material Contract or Designated Contract) is transferred.".

2.11      The expression "to Seller" which appears in line 3 of Clause 3 is
          deleted and replaced with the expression "by Seller".


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2.12      The expression "or" which appears in line 4 of Clause 3 immediately
          prior to the expression "document" is deleted and replaced with ","
          and the following expression is inserted in such line 4 immediately
          following the term "document 23.01.03":

          "or Virtual Data Room document 23.01.04".

2.13      The following expression is inserted in line 6 of Clause 3 immediately
          following the term "of such date":

          ", or (iii) for any matter of which any director or employee of Buyer
          or any Affiliate of Buyer has obtained actual knowledge on or after
          November 30, 2006 as a consequence of, or in connection with, Buyer
          providing management services to which reference is made in Clauses
          6.4 and 6.9 or in relation to the EAST Management Agreement or in
          connection with the obtaining of the consent of any JV Member to which
          reference is made in this Agreement or the process of agreeing any
          documentation needed to effect the transfer of any Remaining Ownership
          Interest".

2.14      Clause 3.13 is deleted and replaced with the following:

          "3.13     Deliberately Omitted".

2.15      The expression "or EAST" is inserted in line 2 of Clause 5.6
          immediately following the expression "Asset Owning Entity".

2.16      The following provision is inserted as Clause 7.1.5:

          "7.1.5    Each of Buyer and Seller shall pay fifty per cent. (50%) of
                    the fees and expenses of (a) any external counsel (i) which
                    acts for any JV Member (other than Seller or any Affiliate
                    of Seller) incurred in connection with the provision of the
                    relevant JV Member's consent to the transfer of Seller's
                    Specified Ownership Interest in the relevant Partnership
                    Asset Owning Entity or the effecting of such transfer or any
                    substitution of a guarantee provided by Seller or any other
                    GATX Retained Entity with a guarantee provided by Buyer, or
                    (ii) which acts for Continental Airlines, Inc. or the Ex-Im
                    2001 Financiers in connection with the arrangements
                    contemplated by this Agreement so far as they relate to the
                    Ex-Im 2001 Financed Aircraft, and (b) Clifford Chance LLP
                    and Vedder, Price, Kaufman & Kammholz, P.C. in relation to
                    the preparation of a bible of transaction documents in
                    relation to the transactions contemplated by this
                    Agreement.".

2.17      The following provisions are inserted as Clauses 7.10.3 and 7.10.4,
          respectively:

          "7.10.3   If pursuant to Clause 7.10.1 Buyer buys Seller's Specified
                    Ownership Interest in the owner trust referred to in Clause
                    7.10.1 and Seller remains a guarantor under the guarantee
                    given by Seller to the ATA Aircraft Financiers and Seller
                    procures the issue of any letter of credit to which
                    reference is made in Section 4.02(a) of the trust agreement
                    to which such Specified Ownership Interest is constituted,
                    Buyer shall promptly, but in any event within three (3)
                    Business Days of receipt of notice from Seller that Buyer is
                    obligated to reimburse



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                    Seller pursuant to this Clause 7.10.3, reimburse to Seller
                    any and all amounts or costs Seller is required to pay or
                    bear under, or in connection with, any indemnity which
                    Seller provides to the issuer of such letter of credit (but
                    not including any amount paid by Seller in order to procure
                    the issue of such letter of credit), together with any
                    expenses (including reasonable expenses of investigation and
                    reasonable attorney's fees and expenses) incurred by Seller
                    in connection therewith (it being understood and agreed that
                    any disputes with respect to any such reimbursement shall be
                    governed in accordance with the provisions of Clause 11.3).

          7.10.4    It is hereby confirmed, for the avoidance of doubt, that
                    following the acquisition of Seller's Specified Ownership
                    Interest in the trust to which reference is made in Clause
                    7.10.1, Buyer shall be able to transfer such Specified
                    Ownership Interest to any other person in accordance with
                    the provisions of the trust agreement pursuant to which such
                    Specified Ownership Interest is constituted without the need
                    for the prior approval of Buyer provided that any such
                    transfer shall not release Buyer from, or otherwise have any
                    effect on, the liability of Buyer under Clause 7.10.2 or
                    Clause 7.10.3 in relation to any payment which Seller is
                    required to make under the guarantee to which reference is
                    made in Clause 7.10.2 or any amount or cost which Seller is
                    required to pay or bear to which reference is made in Clause
                    7.10.3.".

2.18      Clause 7.17 is amended as follows:

                   (a)       the sub-clause forming part thereof which is
                             erroneously numbered "7.10.3" is correctly numbered
                             "7.17.3"; and

                   (b)       the following provision is inserted as Clause
                             7.17.4:

                   "7.17.4   If by April 17, 2007 Seller has not been released
                             from its obligations under any of the Ex-Im 2001
                             Management Agreements, Seller shall formally
                             request the Ex-Im 2001 Financiers to release Seller
                             from each of the Ex-Im 2001 Management Agreements
                             from which Seller has not been released and use all
                             commercially reasonable efforts to procure such
                             releases. In the event that any such release has
                             not been obtained by July 17, 2007, Seller shall
                             within the period of ten (10) days thereafter
                             procure the issue in favour of Seller of a letter
                             of credit issued by Macquarie Bank Limited, or
                             another bank with a credit rating not less than the
                             credit rating then held by Macquarie Bank Limited
                             and otherwise reasonably acceptable to Seller, in
                             the sum equal to the then net present value, as
                             reasonably determined by Seller, of the aggregate
                             fee (based on an arm's length quotation obtained by
                             Seller from a reputable entity (other than GECAS,
                             ILFC or an affiliate of either thereof) generally
                             engaged in providing management and administration
                             services) which Seller would be required to pay to
                             a person reasonably acceptable to Seller to provide
                             the management and administration services required
                             to be provided by Seller under each of the Ex-Im
                             2001 Management Agreements to which Seller remains
                             a party for the then remaining term of the same and
                             able to be drawn


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                             at any time by Seller in the event, and during the
                             continuance, of any Management Agreement Event of
                             Default, such that Seller shall appoint such a
                             person to provide such management and
                             administration services and apply the proceeds of
                             such letter of credit in effecting payment of such
                             aggregate fee.".

2.19      The sign "(*)" which appears in paragraph 27 of Part 2 of Schedule 5
          is deleted.


3.        MISCELLANEOUS

3.1       The provisions of Clauses 13.1, 13.2, 13.3, 13.4, 13.5, 13.6, 13.8 and
          13.10 are hereby deemed to be incorporated herein as if all references
          therein to "this Agreement" were references to this Second
          Supplemental Agreement.

3.2       References to "this Agreement" in the Sale and Purchase Agreement are
          deemed to be references to the Sale and Purchase Agreement as amended
          by this Second Supplemental Agreement.



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IN WITNESS WHEREOF, the parties to this Second Supplemental Agreement have
caused this Second Supplemental Agreement to be duly executed by their
respective authorized officers as of the day and year first above written.


Seller

GATX FINANCIAL CORPORATION

By:              /s/ Robert C. Lyons
     --------------------------------------------
     Name:    Robert C. Lyons
     Title:   Vice President and Chief
              Financial Officer



Buyer

MACQUARIE AIRCRAFT LEASING
LIMITED

By:              /s/ Stephen Moulton
     --------------------------------------------
     Name:    Stephen Moulton
     Title:   Attorney in Fact

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



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