FIFTH AMENDING AGREEMENT IN RESPECT OF THE THIRD AMENDED AND RESTATED GULFSTREAM PARK LOAN AGREEMENT

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Exhibit 10.3

FIFTH AMENDING AGREEMENT IN RESPECT OF THE THIRD AMENDED
AND RESTATED GULFSTREAM PARK LOAN AGREEMENT

         THIS AGREEMENT made as of the 15 day of September, 2008,

BETWEEN:

GULFSTREAM PARK RACING ASSOCIATION, INC.,
a corporation incorporated under the laws of the
State of Florida

(being hereinafter called the " Borrower "),

        OF THE FIRST PART,

– and –

MID ISLANDI SF.,
a partnership formed under the laws of
Iceland, acting through its Zug branch

(being hereinafter called the " Lender "),

        OF THE SECOND PART,

– and –

REMINGTON PARK, INC.,
a corporation incorporated under the laws of the
State of Oklahoma

(being hereinafter called the " Remington Guarantor "),

        OF THE THIRD PART,

– and –

GPRA THOROUGHBRED TRAINING CENTER, INC.,
a corporation incorporated under the laws of the
State of Delaware

(being hereinafter called the " Palm Meadows Guarantor "),

– and –

MAGNA ENTERTAINMENT CORP.,
a corporation incorporated under the laws of the
State of Delaware

(being hereinafter called " MEC "), (the Remington Guarantor,
the Palm Meadows Guarantor and MEC being hereinafter collectively
called the " Original Guarantors "),

        OF THE FOURTH PART,

– and –

GULFSTREAM COMMERCIAL ENTERPRISES, INC.,
a corporation incorporated under the laws of the
State of Florida

(being hereinafter called the " Gulfstream Commercial Guarantor "
(the Original Guarantors and the Gulfstream Commercial Guarantor
being hereinafter called the " Guarantors "),

        OF THE FIFTH PART.

        WHEREAS the Lender, as lender, the Borrower, as borrower, and the Original Guarantors, as guarantors, are parties to a Third Amended and Restated Gulfstream Park Loan Agreement made as of December 22, 2006 (such Third Amended and Restated Gulfstream Park Loan Agreement, as amended by a First Amending Agreement in respect of the Third Amended and Restated Gulfstream Park Loan Agreement dated as of August 3, 2007, and as amended by a Second Amending Agreement (the " Second Amending Agreement ") in respect of the Third Amended and Restated Gulfstream Park Loan Agreement dated as of September 11, 2007, as amended by a Third Amending Agreement (the " Third Amending Agreement ") in respect of the Third Amended and Restated Gulfstream Loan Agreement dated as of May 23 ^rd , 2008, as amended by a Fourth Amending Agreement (the " Fourth Amending Agreement ") in respect of the Third Amended and Restated Gulfstream Loan Agreement dated as of August 13, 2008, and as the Third Amended and Restated Gulfstream Park Loan Agreement may be further amended, modified, renewed or replaced from time to time, being referred to herein the " Gulfstream Park Loan Agreement ");

        AND WHEREAS on September 11, 2007, MEC's Board of Directors approved and adopted a plan (the " MEC Debt Elimination Plan ") (referenced in the Second Amending Agreement as the " Borrower Restructuring Plan ") to restructure MEC and its subsidiaries (including the Borrower) and to revise the business plan of MEC and its subsidiaries (including the Borrower);

2

        AND WHEREAS the MEC Debt Elimination Plan contemplated the sale of assets including, without limiting the generality of the foregoing, certain of those Properties owned by the Borrower that constitute collateral for the Loan;

        AND WHEREAS the sale of assets under the MEC Debt Elimination Plan continues to take longer than originally contemplated and, although MEC continues to take steps to implement the MEC Debt Elimination Plan, it does not expect to execute the MEC Debt Elimination Plan on the originally contemplated time schedule, if at all;

        AND WHEREAS on March 31, 2008, the Board of Directors of MI Developments Inc. (" MID "), an affiliate of MEC and the controlling shareholder of MEC, received a reorganization proposal on behalf of various shareholders of MID that would, among other things, alter the relationship between MID and MEC;

        AND WHEREAS on June 27, 2008, MID announced that, in light of shareholder discussions relating to potential amendments to the reorganization proposal, the special meeting of MID shareholders to consider the reorganization proposal, previously called for July 24, 2008, was being postponed;

        AND WHEREAS discussions between MID and various of its shareholders relating to potential amendments to the reorganization proposal are ongoing, and, given that no consensus has been reached with respect to such amendments, MID intends to continue to explore a range of alternatives with respect to its investment in MEC;

        AND WHEREAS on August 22, 2008, MID announced that it had retained GMP Securities L.P. as a financial advisor to MID management to liaise with shareholders in an attempt to develop a consensus on how best to reorganize MID;

        AND WHEREAS pursuant to the Third Amending Agreement, the parties to the Gulfstream Park Loan Agreement amended the Gulfstream Park Loan Agreement to: (i) revise certain representations and covenants relating to implementation of MEC Debt Elimination Plan; (ii) to extend from May 31, 2008 to August 31, 2008 the deadline for repayment of $100 m