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                                                                     Exhibit 5.1

                          [KIRKLAND & ELLIS LETTERHEAD]

                                 March 5, 2003


MDP Acquisitions plc
and MDCP Acquisitions I, as Guarantor of the Senior Exchange Notes
Arthur Cox Building
Earlsfort Terrace
Dublin 2
Ireland


         Re:      Registration Statement on Form F-4
                  File No. 333-101456

Ladies and Gentlemen:


         We are issuing this opinion letter in our capacity as special
legal counsel to MDP Acquisitions plc, an Irish public limited company (the
"Issuer"), and MDCP Acquisitions I, an Irish unlimited public company (such
guarantor is hereinafter referred to as the "Guarantor" and the Guarantor,
together with the Issuer, are hereinafter referred to as the "Registrants"),
in connection with the proposed registration by the Issuer of E350,000,000 in
aggregate principal amount of the Issuer's 10 1/8% Senior Notes due 2012,
Series B (the "Euro Senior Exchange Notes"), $545,000,000 in aggregate
principal amount of the Issuer's 9 5/8% Senior Notes due 2012, Series B (the
"Dollar Senior Exchange Notes" and together with the Euro Senior Exchange
Notes, the "Senior Exchange Notes"), E103,831,945 in aggregate principal
amount of the Issuer's 15.5% Subordinated Notes due 2013, Series B (the "Euro
Subordinated Exchange Notes"), and $155,747,917 in aggregate principal amount
of the Issuer's 15.5% Subordinated Notes due 2013, Series B (the "Dollar
Subordinated Exchange Notes" and together with the Euro Senior Exchange
Notes, the Dollar Senior Exchange Notes and the Euro Subordinated Exchange
Notes, the "Exchange Notes"), pursuant to a Registration Statement on Form
F-4 filed with the Securities and Exchange Commission (the "Commission") as
of the date hereof, under the Securities Act of 1933, as amended (the "Act")
(such Registration Statement, as amended or supplemented, is hereinafter
referred to as the "Registration Statement").

         The obligations of the Issuer under the Senior Exchange Notes will be
guaranteed by the Guarantor (the "Guarantees"). The Euro Senior Exchange Notes
and the Guarantees are to be issued pursuant to the Indenture (as supplemented,
the "Euro Senior Notes Indenture"), dated as of September 30, 2002, among the
Issuer, the Guarantor and Deutsche Bank Trust Company Americas, as trustee. The
Euro Senior Exchange Notes and the Guarantees are to be issued in exchange for
and in replacement of the Issuer's outstanding 10 1/8% Senior Notes due 2012
(the "Euro Senior Old Notes"), of which E350,000,000 in aggregate principal
amount is outstanding. The Dollar Senior Exchange Notes and the Guarantees are
to be issued pursuant to the Indenture (as supplemented, the "Dollar Senior
Notes Indenture"), dated as of September 30, 2002, among the Issuer, the
Guarantor and Deutsche Bank Trust Company Americas, as trustee. The Dollar

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Senior Exchange Notes and the Guarantees are to be issued in exchange for and in
replacement of the Issuer's outstanding 9 5/8% Senior Notes due 2012 (the
"Dollar Senior Old Notes" and together with the Euro Senior Old Notes, the
"Senior Old Notes"), of which $545,000,000 in aggregate principal amount is
subject to the exchange offer pursuant to the Registration Statement.

         The Euro Subordinated Exchange Notes are to be issued pursuant to
the Indenture (as supplemented, the "Euro Subordinated Notes Indenture"),
dated as of October 2, 2002, among the Issuer and Deutsche Bank Trust Company
Americas, as trustee. The Euro Subordinated Exchange Notes are to be issued
in exchange for and in replacement of the Issuer's outstanding 15.5%
Subordinated Notes due 2013 (the "Euro Subordinated Old Notes"), of which
E103,831,945 in aggregate principal amount is outstanding. The Dollar
Subordinated Exchange Notes are to be issued pursuant to the Indenture (as
supplemented, the "Dollar Subordinated Notes Indenture"), dated as of October
2, 2002, among the Issuer and Deutsche Bank Trust Company Americas, as
trustee. The Dollar Subordinated Exchange Notes are to be issued in exchange
for and in replacement of the Issuer's outstanding 15.5% Subordinated Notes
due 2013 (the "Dollar Subordinated Old Notes" and together with the Euro
Subordinated Old Notes, the "Subordinated Old Notes"), of which $155,747,917
in aggregate principal amount is outstanding.

         In connection therewith, we have examined originals, or copies
certified or otherwise identified to our satisfaction, of such documents,
corporate records and other instruments as we have deemed necessary for the
purposes of this opinion, including (i) resolutions of the Registrants with
respect to the issuance of the Exchange Notes and the Guarantees, (ii) the
Indentures, (iii) the Registration Statement, (iv) the Registration Rights
Agreements, dated as of September 30, 2002, by and among the Registrants and
Deutsche Bank AG London and Merrill Lynch International, as representatives of
the initial purchasers, relating to the senior notes, and (v) the Registration
Rights Agreements, dated as of October 2, 2002, by and among the Issuer and
Deutsche Bank AG London and Merrill Lynch International, as representatives of
the initial purchasers, relating to the subordinated notes.

         For purposes of this opinion, we have assumed the authenticity of all
documents submitted to us as originals, the conformity to the originals of all
documents submitted to us as copies and the authenticity of the originals of all
documents submitted to us as copies. We have also assumed the genuineness of the
signatures of persons signing all documents in connection with which this
opinion is rendered, the authority of such persons signing on behalf of the
parties thereto and the due authorization, execution and delivery of all
documents by the parties thereto. As to any facts material to the opinions
expressed herein which we have not independently established or verified, we
have relied upon statements and representations of officers and other
representatives of the Registrants and others.

         Our opinion expressed below is subject to the qualifications that we
express no opinion as to the applicability of, compliance with, or effect of (i)
any bankruptcy, insolvency, reorganization, fraudulent transfer, fraudulent
conveyance, moratorium or other similar law affecting the enforcement of
creditors' rights generally, (ii) general principles of equity (regardless of
whether enforcement is considered in a proceeding in equity or at law), (iii)
public policy considerations which may limit the rights of parties to obtain
certain remedies and (iv) any laws except the laws of the State of New York and
the federal laws of the United States of America.


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         Based upon and subject to the assumptions, qualifications,
exclusions and limitations and the further limitations set forth below, we
are of the opinion that when (i) the Registration Statement becomes
effective, (ii) the Indentures have been duly qualified under the Trust
Indenture Act of 1939, as amended, and (iii) the Exchange Notes have been
duly executed and authenticated in accordance with the provisions of the
Indentures and duly delivered to the holders thereof in exchange for the
Senior Old Notes and the Subordinated Old Notes, the Exchange Notes will be
validly issued and binding obligations of the Issuer and the Guarantees will
be validly issued and binding obligations of the Guarantor.

         We hereby consent to the filing of this opinion with the commission as
Exhibit 5.1 to the Registration Statement. We also consent to the reference to
our firm under the heading "Legal Matters" in the Registration Statement. In
giving this consent, we do not thereby admit that we are in the category of
persons whose consent is required under Section 7 of the Act or the rules and
regulations of the Commission.

         Our advise on every legal issue addressed in this letter is based
exclusively on the law of the State of New York or the federal law of the United
States. For purposes of our opinion that the Exchange Notes will be validly
issued and binding obligations of the Issuer and the Guarantees will be validly
issued and binding obligations of the Guarantor, we have relied upon the opinion
of Arthur Cox that the Indentures have been duly authorized, executed and
delivered and the Exchange Notes and Guarantees have been duly authorized by
each of the Registrants, as applicable, in accordance with the applicable laws,
rules or regulations of Ireland.

         This opinion is limited to the specific issues addressed herein, and no
opinion may be inferred or implied beyond that expressly stated herein. We
assume no obligation to revise or supplement this opinion should the present
laws of the State of New York or the federal law of the United States be changed
by legislative action, judicial decision or otherwise.

         This opinion is furnished to you in connection with the filing of the
Registration Statement and is not to be used, circulated, quoted or otherwise
relied upon for any other purpose.

                                                  Sincerely,

                                                 /s/ Kirkland & Ellis

                                                  Kirkland & Ellis


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