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                                                                    EXHIBIT 4.15

       SUPPLEMENTAL INDENTURE, dated as of February 14, 2003 (the "Amendment"),
among (i) MDP Acquisitions plc, a public limited company incorporated under the
laws of Ireland and having its registered office at Arthur Cox Building,
Earlsfort Center, Earlsfort Terrace, Dublin 2, Ireland (the "Company"), (ii)
MDCP Acquisitions I, a direct subsidiary of the Company incorporated under the
laws of Ireland and having its registered office at Arthur Cox Building,
Earlsfort Center, Earlsfort Terrace, Dublin 2, Ireland (the "Subsidiary
Guarantor") and (iii) Deutsche Bank Trust Company Americas, a banking
corporation organized under the laws of the State of New York (the "Trustee").
Unless otherwise defined herein, capitalized terms used herein but not defined
shall have the meanings given to such terms in the Indenture (as hereinafter
defined).

                               W I T N E S S E T H

       WHEREAS, the Company, the Subsidiary Guarantor and the Trustee are
parties to that certain Euro Indenture dated as of September 30, 2002 (the
"Indenture") for its 10 1/8% Senior Notes due 2012;

       WHEREAS, pursuant to the Indenture, the Company issued Original Notes on
September 30, 2002;

       WHEREAS, the Company desires that the Indenture be amended (i) to cure a
defect in the Indenture and (ii) to make changes that will provide additional
rights and benefits to Holders of Additional Notes in order that Holders of
Additional Notes and Holders of the Original Notes have the same rights under
the Indenture, and which will not adversely affect the legal rights under the
Indenture of any Holder of Original Notes or Additional Notes;

       WHEREAS, the Company, the Subsidiary Guarantor and the Trustee may,
subject to the conditions set forth in Sections 9.1 and 9.6 of the Indenture,
amend the Indenture (i) to cure any ambiguity, defect, error or inconsistency,
or (ii) to make any change that would provide any additional rights or benefits
to the Holders of the Notes or that does not adversely affect the legal rights
under the Indenture of any such Holder;

       WHEREAS, the Company is representing to the Trustee that the conditions
to this Amendment, as set forth in Section 9.1 and 9.6 of the Indenture, have
been satisfied by the Company;

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                                                                               2

       NOW THEREFORE, in consideration of the premises and mutual covenants
herein contained, the parties hereto agree the following.

       1.     AMENDMENT TO ARTICLE I OF THE INDENTURE. Article I of the
Indenture is hereby amended by:

       (a)    deleting the words:

       ""PRIORITY AGREEMENT" means the Priority Agreement, dated as of September
       16, 2002, as amended, modified or supplemented from time to time, among
       the Senior Creditors (as defined therein), the Company, Parent, the
       Subsidiary Guarantor and the other parties thereto from time to time."

       and substituting therefor the words:

       ""PRIORITY AGREEMENT" means (i) the Priority Agreement, dated as of
       September 16, 2002, (ii) the Priority Agreement dated as of February 14,
       2003 and (iii) any other priority agreement executed in connection with
       the issuance and sale of Additional Notes under the Indenture, in each
       case, as amended, modified or supplemented from time to time, among the
       Senior Creditors (as defined therein), the Company, Parent, the
       Subsidiary Guarantor and the other parties thereto from time to time."

       (b)    deleting the words:

       ""INTERCOMPANY LOAN AGREEMENT" means that agreement, dated as of
       September 16, 2002, as amended, modified or supplemented from time to
       time, between the Company and the Subsidiary Guarantor, providing for a
       loan from the Company to the Subsidiary Guarantor in the amount of the
       gross proceeds of the offering of Notes and the Subordinated PIK
       Securities."

       and substituting therefor the words:

       ""INTERCOMPANY LOAN AGREEMENT" means (i) that agreement, dated as of
       September 16, 2002, as amended, modified or supplemented from time to
       time, between the Company and the Subsidiary Guarantor, providing for a
       loan from the Company to the Subsidiary Guarantor in the amount of the
       gross proceeds of the offering of the Original Notes and the Subordinated
       PIK Securities, and (ii) any other agreement that may be entered into
       from time to time, as may be amended, modified or supplemented from time
       to time, between the Company and the Subsidiary Guarantor for an advance
       of the aggregate principal amount of any Additional Notes issued and sold
       under the Indenture."

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                                                                               3

       2.     AMENDMENT TO SECTION 8.5(1)(b) OF THE INDENTURE. Section 8.5(1)(b)
of the Indenture is hereby amended by:

       (a)    inserting, after the words "making of a notice of redemption or
              otherwise, and", the words "the Company has irrevocably deposited
              with the Trustee as trust funds in trust".

       (b)    inserting, after the words "maturity or redemption", the words
              "PROVIDED, HOWEVER, in the event a petition for relief under any
              Bankruptcy Law is filed with respect to the Company within 91 days
              after the deposit and the Trustee is required to return the moneys
              then on deposit with the Trustee to the Company, the obligations
              of the Company under this Indenture with respect to such Notes
              shall not be deemed terminated or discharged".

       3.     INDEMNITY. In addition to, and not in lieu of, the indemnification
provided by the Company in the Indenture, the Company shall indemnify the
Trustee for, and hold the Trustee harmless against, any and all loss, damage,
claim, expense or liability including taxes (other than taxes based on the
income of the Trustee) incurred by the Trustee in connection with the execution
of this Amendment and performance of its duties under this Amendment, including
the reasonable expenses and attorneys' fees and expenses of defending itself
against any claim of liability arising hereunder. The Trustee shall notify the
Company promptly of any claim asserted against the Trustee for which it may seek
indemnity. However, the failure by the Trustee to so notify the Company shall
not relieve the Company of its obligations hereunder. The Company shall defend
the claim and the Trustee or such Agent shall cooperate in the defense (and may
employ its own counsel reasonably satisfactory to the Trustee) at the Company's
expense. The Trustee may have separate counsel and the Company shall pay the
reasonable fees and expenses of such counsel. The Company need not pay for any
settlement made without its written consent, which consent shall not be
unreasonably withheld.

       4.     EFFECTIVENESS. This Amendment shall become effective when executed
by each of the Company, the Subsidiary Guarantor and the Trustee.

       5.     EFFECT ON INDENTURE. Except as expressly amended hereby, the
Indenture shall continue to be and shall remain in full force and effect.

       6.     COUNTERPART ORIGINALS. All parties hereto may sign any number of
copies of this Amendment. Each signed copy or counterpart shall be an original,
but all of them together shall represent one and the same agreement.

       7.     GOVERNING LAW. THIS AMENDMENT, AND THE RIGHTS AND DUTIES OF THE
PARTIES HEREUNDER, SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE
LAWS OF THE STATE OF NEW YORK.

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       IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed, as of the date first written above.

                                           MDP ACQUISITIONS PLC


                                           PRESENT when the Common Seal of MDP
                                           Acquisitions plc was affixed hereto:-


                                           By: /s/ GARY W. McGANN
                                               -------------------
                                           Name: Gary W. McGann
                                           Title: Director


                                           By: /s/ IAN J. CURLEY
                                               -------------------
                                           Name: Ian J. Curley
                                           Title: Director/Secretary

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                                                                               5

                                         MDCP ACQUISITIONS I


                                         PRESENT when the Common Seal of
                                         MDP Acquisitions I was affixed hereto:-


                                         By:   /s/ GARY W. McGANN
                                               -------------------
                                         Name: Gary W. McGann
                                         Title: Director


                                         By:   /s/ IAN J. CURLEY
                                               -------------------
                                         Name: Ian J. Curley
                                         Title: Director/Secretary

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                                                                               6

                                         DEUTSCHE BANK TRUST COMPANY
                                         AMERICAS, as Trustee


                                         By:   /s/ WANDA CAMACHO
                                               -------------------
                                         Name: Wanda Camacho
                                         Title: Vice President