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                                                                   EXHIBIT 99.28


                SUPPLEMENT TO MASTER SECURITIES PLEDGE AGREEMENT


This is a Supplement made as of May 31, 2001 to the securities pledge agreement
made as of August 10, 1998 by certain persons to Canadian Imperial Bank of
Commerce, as Lender (the "Pledge Agreement"). The provisions of the Pledge
Agreement shall apply, mutatis mutandis, to this Supplement. Capitalized terms
used but not otherwise defined in this Supplement have the meanings specified in
the Pledge Agreement.

For valuable consideration, each of the undersigned (each a "New Pledgor")
severally (and not jointly, or jointly and severally) agrees with the Lender as
follows:

1.     Each New Pledgor acknowledges that it has received and reviewed a copy of
the Pledge Agreement and the Credit Documents in existence on the date of this
Supplement, and confirms that it is executing and delivering this Supplement to
the Lender pursuant to Section 21 of the Pledge Agreement.

2.     Effective from and after the date this Supplement is executed and
delivered to the Lender by any New Pledgor (and irrespective of whether this
Supplement has been executed and delivered by any other person), such New
Pledgor is, and shall be deemed for all purposes to be, a Pledgor under the
Pledge Agreement with the same force and effect, and subject to the same
agreements, representations, guarantees, indemnities, liabilities and
obligations, as if such New Pledgor was, effective as of the date of this
Supplement, an original signatory to the Pledge Agreement as a Pledgor. In
furtherance of the foregoing, each New Pledgor severally (and not jointly, or
jointly and severally) as security for the payment and performance of the
Obligations of such New Pledgor (including any Obligations that would become due
but for any automatic stay under the provisions of the Bankruptcy and Insolvency
Act (Canada), the United States Bankruptcy Code or any analogous provisions of
any other applicable law in Canada, the United States of America or any other
jurisdiction) hereby assigns and pledges to the Lender and grants to the Lender
a continuing security interest in, the Pledged Collateral of such New Pledgor.

3.     Upon this Supplement bearing the signature of any of person claiming to
have authority to bind a New Pledgor coming into the hands of the Lender, and
irrespective of whether this Supplement or the Pledge Agreement has been
executed by any other person, this Supplement will be deemed to be finally and
irrevocably executed and delivered by, and be effective and binding on, and
enforceable against, such New Pledgor free from any promise or condition
affecting or limiting the obligations of such New Pledgor and such New Pledgor
shall be, and shall be deemed for all purposes to be, a Pledgor under the Pledge
Agreement. No statement, representation, agreement or promise by any officer,
employee or agent of the Lender forms any part of this Supplement or the Pledge
Agreement or has induced the making of this Supplement or the Pledge Agreement
by any New Pledgor or in any way affects any of the Obligations of any New
Pledgor.



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IN WITNESS OF WHICH this Supplement has been duly executed and delivered by each
New Pledgor as of the date indicated on the first page of this Supplement.


                                 3055851 NOVA SCOTIA COMPANY



                                 by:  ______________________________
                                 name:
                                 title:


                                 3055852 NOVA SCOTIA COMPANY



                                 by:  ______________________________
                                 name:
                                 title: