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                                                                     EXHIBIT 4.5

                               FIRST AMENDMENT TO
                       SERIES 2003-1 INDENTURE SUPPLEMENT

         This First Amendment to Series 2003-1 Indenture Supplement, dated as of
November 17, 2003 (this "Amendment"), by and between FIRST NATIONAL MASTER NOTE
TRUST, a Delaware statutory trust, as issuer (the "Issuer"), and THE BANK OF NEW
YORK, a New York banking corporation, as trustee (the "Indenture Trustee").
Terms used but not defined herein shall have the meanings assigned to such terms
in that certain Series 2003-1 Indenture Supplement, dated as of March 20, 2003,
by and between the Issuer and the Indenture Trustee (as amended, the
"Supplement").

         In consideration of the mutual agreements herein contained, each party
agrees as follows for the benefit of the other parties and the Series 2003-1
Noteholders:

         Section 1. Amendment of the Supplement. The Supplement shall be amended
as set forth in this Amendment.

         Section 2. Amendments. The definitions of Excess Servicing Fee, Group
One and Servicer Interchange are hereby amended and restated to read in their
entirety as follows:

                           "Excess Servicing Fee" means, for each Distribution
                  Date following a Servicer Default and the appointment of a
                  Successor Servicer, an amount equal to one-twelfth of the
                  product of the Collateral Amount as of the last day of the
                  preceding Monthly Period and the excess of the market rate
                  servicing fee percentage determined by Indenture Trustee over
                  the Series Servicing Fee Percentage, plus, if the Indenture
                  Trustee is the Successor Servicer, an amount equal to the
                  amount of the reduction to the applicable Noteholder Servicing
                  Fee pursuant to the second proviso in Section 3.01 which is
                  attributable to the fact that Interchange included in
                  Collections of Finance Charge Receivables for the related
                  Monthly Period is less than Servicer Interchange for such
                  Monthly Period. Indenture Trustee may determine the market
                  rate servicing fee percentage by soliciting three or more
                  written bids from qualified successor servicers and averaging
                  the rates offered in the bids.

                           "Group One" means Series 2003-1, the outstanding PSA
                  Series (other than any Series represented by the Collateral
                  Certificate) and each other Series specified in the related
                  Indenture Supplement to be included in Group One.

                           "Servicer Interchange" means, with respect to any
                  Monthly Period, an amount equal to one-twelfth of the product
                  of (a) 1.50% and (b) the Collateral Amount as of the last day
                  of the preceding Monthly Period; provided, however, that
                  Servicer Interchange for the May, 2003 Distribution Date shall
                  be $575,342.

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         Section 3. Execution in Counterparts. This Amendment may be executed in
any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed and delivered shall be deemed to be
an original and all of which taken together shall constitute but one and the
same instrument.

         Section 4. Governing Law. This Amendment shall be governed by and
construed in accordance with the governing law specified in the Supplement.

         Section 5. Limitation of Liability. Notwithstanding any other provision
herein or elsewhere, this Amendment has been executed and delivered by
Wilmington Trust Company, not in its individual capacity, but solely in its
capacity as Owner Trustee of the Trust, in no event shall Wilmington Trust
Company, in its individual capacity, have any liability in respect of the
representations, warranties, or obligations of Issuer hereunder or under any
other document, as to all of which recourse shall be had solely to the assets of
Issuer, and for all purposes of this Agreement and each other document, Owner
Trustee (as such or in its individual capacity) shall be subject to, and
entitled to the benefits of, the terms and provisions of the Trust Agreement.

                                        2

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         IN WITNESS WHEREOF, the undersigned have caused this First Amendment to
Series 2003-1 Indenture Supplement to be duly executed as of the date first
above written.

                                    FIRST NATIONAL MASTER NOTE TRUST, as Issuer

                                    By  Wilmington Trust Company, not in its
                                        individual capacity, but solely as Owner
                                        Trustee

                                    By /s/ Janel R. Havrilla
                                       -----------------------------------------
                                    Name Janel R. Havrilla
                                    Title Financial Services Officer

                                    THE BANK OF NEW YORK,
                                    as Indenture Trustee

                                    By /s/ Mary L. Collier
                                       -----------------------------------------
                                    Name Mary L. Collier
                                    Title Agemt

Acknowledged and Accepted:

FIRST NATIONAL BANK OF OMAHA,
as Servicer

By /s/ Jean L. Koenck
   ----------------------------------------------
Name Jean L. Koenck
Title Vice President

FIRST NATIONAL FUNDING LLC,
as Transferor

By First National Funding Corporation,
   its Managing Member

By /s/ Jean L. Koenck
   ----------------------------------------------
Name Jean L. Koenck
Title Senior Vice President

                        FIRST AMENDMENT TO SERIES 2003-1
                       INDENTURE SUPPLEMENT SIGNATURE PAGE