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                                                                    EXHIBIT 3.13

                                STATE OF DELAWARE

                        OFFICE OF THE SECRETARY OF STATE




         I, EDWARD J. FREEL, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO
HEREBY CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF
INCORPORATION OF "MFT ACQUISITION, CORP.", FILED IN THIS OFFICE ON THE FIRST DAY
OF AUGUST, A.D. 2000, AT 9 O'CLOCK A.M.

         A FILED COPY OF THIS CERTIFICATE HAS BEEN FORWARDED TO THE KENT COUNTY
RECORDER OF DEEDS.

                                        /s/ Edward J. Freel
                                        ----------------------------------------
                                        Edward J. Freel, Secretary of State


3265208  8100                                         AUTHENTICATION:   0594900
001388212                                                       DATE:   08-02-00


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                          CERTIFICATE OF INCORPORATION
                                       OF
                             MFT ACQUISITION, CORP.

         FIRST: The name of the corporation is MFT Acquisition, Corp. (the
"Corporation").

         SECOND: The name and address of the registered agent for service of
process on the Corporation in the State of Delaware is Lexis Document Services,
Inc., 30 Old Rudnick Lane, Suite 100, Dover, Kent County, Delaware, 19904.

         THIRD: The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of Delaware as the same exists or may hereafter be amended ("Delaware Law").

         FOURTH: The class of stock to be issued will be common par value $.01
per share. The total number of shares of stock authorized is one thousand
(1,000) and the number of shares proposed to be issued is one hundred (100).

         FIFTH: The name and mailing address of the incorporator is as follows:


<TABLE>
<CAPTION>

         Name                                 Mailing Address
         ----                                 ---------------
<S>                                        <C>
         Olga Stambler                        Bell, Boyd & Lloyd
                                              Three First National Plaza
                                              70 West Madison Street, Suite 3100
                                              Chicago, Illinois 60602-4207

</TABLE>

         SIXTH: The Corporation is to have perpetual existence.

         SEVENTH: The original bylaws of the Corporation shall be adopted by the
incorporator. Thereafter, in furtherance and not in limitation of the powers
conferred by statute, the board of directors is expressly authorized to make,
alter or repeal the bylaws of the Corporation.

         EIGHTH: Meetings of stockholders may be held within or without the
State of Delaware, as the bylaws may provide. The books of the Corporation may
be kept (subject to any provision contained in the statutes) outside the State
of Delaware at such place or places as may be designated from time to time by
the board of directors or in the bylaws of the Corporation. Elections of
directors need not be by written ballot unless the bylaws of the Corporation
shall so provide.


                                                         STATE OF DELAWARE
                                                        SECRETARY OF STATE
                                                     DIVISION OF CORPORATIONS
                                                     FILED 09:00 AM 08/01/2000
                                                         001388212-3265208
                                         492579.1
                                         07431-2024

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         NINTH: (1) Each person who is or was a director or officer of the
Corporation or a subsidiary of the Corporation and each person who serves or
served at the request of the Corporation as a director or officer of another
corporation, partnership, joint venture, true or other enterprise (and the
heirs, executors, administrators and estates of any such persons), shall
be indemnified by the Corporation in accordance with, and to the fullest extent
authorized by, the provisions of the Delaware General Corporation Law as it may
from time to time be amended. Each person who is or was an employee or agent of
another corporation, partnership, joint venture, trust or other enterprise, may
be similarly indemnified at the discretion of the board of directors.

(2) No director shall be personally liable to the Corporation or its
stockholders for monetary damages for any breach of fiduciary duty by such
director as a director. Notwithstanding the foregoing sentence, a director shall
be liable to the extent provided by applicable law (i) for breach of the
director's duty of loyalty to the Corporation or its stockholders, (ii) for acts
or omissions not in good faith or which involve intentional misconduct or a
knowing violation of the law, (iii) pursuant to Section 174 of the Delaware
General Corporation Law, or (iv) for any transaction from which the director
derived an improper personal benefit.

(3) No amendment to or repeal of this Article NINTH shall apply to or have any
effect on the right to indemnification or liability or alleged liability of any
person who is or was a director or officer of the Corporation or a subsidiary of
the Corporation or any person who serves or served at the request of the
Corporation as a director or officer of another corporation, partnership, joint
venture, trust or other enterprise (or the heirs, executors, administrators and
estates of any such persons), for or with respect to any acts or omissions of
such person occurring prior to such amendment.

         TENTH: The Corporation reserves the right to amend this Certificate of
Incorporation in any manner permitted by Delaware Law and, with the sole
exception of those rights and powers conferred under the above ARTICLE NINTH,
all rights and powers conferred herein on stockholders, directors and officers,
if any, are subject to this reserved power.

         IN WITNESS WHEREOF, the undersigned has made, signed and acknowledged
this Certificate this 31st day of July, 2000.

                                      /s/Olga Stambler
                                      ------------------------------------------
                                      Olga Stambler
                                      Incorporator


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                            CERTIFICATE OF CORRECTION
                                     TO THE
                          CERTIFICATE OF INCORPORATION
                                       OF
                             MFT ACQUISITION, CORP.

         MFT Acquisition, Corp. (the "Corporation"), a corporation organized and
existing under and by virtue of the General Corporation Law of the State of
Delaware, DOES HEREBY CERTIFY:

         1. The name of the Corporation is MFT Acquisition, Corp.

         2. The Certificate of Incorporation of the Corporation was filed with
the Secretary of State of Delaware on August 1, 2000 and said Certificate
requires correction as permitted by subsection (f) of Section 103 of the General
Corporation Lave of the State of Delaware.

         3. The inaccuracy or defect of said Certificate of Incorporation to be
corrected is that paragraph SECOND of said Certificate of Incorporation
inadvertently omitted to state that the address of the corporation's registered
agent in the State of Delaware is the address of the Corporation's registered
office in the State of Delaware.

         4. The Certificate of Incorporation should be corrected to delete
paragraph SECOND in its entirety and add the following in lieu thereof.

                  SECOND: The address of the Corporation's registered office in
                  the State of Delaware is 30 Old Rudnick Lane, Suite 100, City
                  of Dover, County of Kent, Delaware, 19904. The name of its
                  registered agent at such address is Lexis Document Services,
                  Inc.

         IN WITNESS WHEREOF, MFT Acquisition, Corp. has caused this Certificate
of Correction to the Certificate of Incorporation to be executed this 18th day
of October, 2002.

                                                     MFT Acquisition, Corp.

                                                     By: /s/ Garry Leach
                                                         -----------------------
                                                     Name: Garry Leach
                                                     Title: Vice President

STATE OF DELAWARE
SECRETARY OF STATE
DIVISION OF CORPORATIONS
FILED 09:00 AM 10/22/2002
020649419 - 2166817