ACKNOWLEDGEMENT AND AGREEMENT BY GUARANTOR

Exhibit 2.1

THIS AMENDING AGREEMENT is made as of the 3rd day of April, 2007.

BETWEEN:

WHEREAS the parties hereto entered into a credit agreement dated as of April 4, 2006 (such credit agreement being herein referred to as the “Credit Agreement”);

AND WHEREAS the parties hereto wish to amend the Credit Agreement to reflect the extension pursuant to Section 2.3(c) of the Credit Agreement of the first date referred to in clause (a) of the definition of “Term Date” in the Credit Agreement to April 2, 2008;

NOW THEREFORE THIS AGREEMENT WITNESSES that in consideration of the mutual covenants and agreements hereinafter contained and other good and valuable consideration (the receipt and sufficiency whereof is hereby acknowledged by each of the parties hereto) the parties do hereby respectively covenant and agree as follows:

“Term Date” means the earlier of (a) April 2, 2008 or, if such date is extended pursuant to Section 2.3(c), the date to which it has been extended, and (b) the Amortization Date;

IN WITNESS WHEREOF this amending agreement has been executed by the parties hereto.

ACKNOWLEDGEMENT AND AGREEMENT BY GUARANTOR

FOR GOOD AND VALUABLE CONSIDERATION (the receipt and sufficiency whereof is hereby acknowledged by the undersigned) the undersigned, Hub International Limited, does hereby acknowledge the terms and conditions of the amending agreement between Hub International Limited Partnership and Bank Of Montreal set out above and further acknowledges and agrees that, after giving full force and effect to such amending agreement, the Guarantee entered into as of April 4, 2006 by the undersigned in favour of Bank of Montreal (the “Guarantee”) remains in all respects in full force and effect on this date, binding in accordance with its terms on, and enforceable against, the undersigned and, without limiting the foregoing,

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the undersigned hereby acknowledges and agrees that the execution and delivery by Bank of Montreal of such amending agreement shall not constitute or operate as an amendment, modification or waiver of any provision of, or of the strict observance, performance or compliance by the undersigned with, any term, covenant, condition or agreement contained in the Guarantee, or as an indulgence or consent granted by Bank of Montreal to any departure by the undersigned from any term, covenant, condition or agreement contained in the Guarantee.

IN WITNESS WHEREOF this acknowledgement and agreement has been executed by the undersigned as of the date of the amending agreement between Hub International Limited Partnership and Bank Of Montreal set out above.

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