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                                                                     Exhibit 4.2

                          REGISTRATION RIGHTS AGREEMENT


                  REGISTRATION RIGHTS AGREEMENT, dated as of December 18, 1998,
between TA I Limited (the "COMPANY"), a limited liability company organized
under the laws of England and Wales, and Profit Sharing (Overseas), Limited
Partnership ("PROFIT SHARING"), an Alberta, Canada limited partnership.

                                    RECITALS

                  Pursuant to a Contribution and Share Subscription Agreement,
dated as of July 22, 1998 (the "CONTRIBUTION AGREEMENT"), among the Company, TA
II Limited, TA III plc, Trinity Acquisition plc, KKR 1996 Fund (Overseas),
Limited Partnership and Profit Sharing, Profit Sharing made equity contributions
of L165,000,000 in the aggregate to the Company.

                  The Company desires to provide to the Holders rights to
registration under the Securities Act of Registrable Securities, on the terms
and subject to the conditions set forth herein.

                                    AGREEMENT

                  1. DEFINITIONS. As used in this Agreement, the following
capitalized terms shall have the following respective meanings:

                  "ADSs": American Depositary Shares, each representing one or
         more Ordinary Shares and represented by American Depositary Receipts of
         the Company.

                  "CARRIER REGISTRATION RIGHTS AGREEMENT": The Registration
         Rights Agreement, dated as of July 22, 1998, as such agreement may be
         amended from time to time, to which the Company is a party.

                  "CLASS": The Ordinary Shares, together with any ADSs
         representing Ordinary Shares.

                  "DEMAND PARTY": (a) Profit Sharing or (b) any other Holder or
         Holders, including, without limitation, any present or future general
         partner of Profit Sharing, or any general or limited partner of any
         general partner thereof, that may become an assignee of Profit
         Sharing's rights hereunder; PROVIDED that to be a Demand Party under
         this clause (b), a Holder or Holders must either individually or in
         aggregate with all other Holders with whom it is acting together to
         demand registration own at least 1% of the total number of Registrable
         Securities.

                  "EXCHANGE ACT": The Securities Exchange Act of 1934, as
         amended, or any similar federal statute then in effect, and a reference
         to a particular section thereof shall


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         be deemed to include a reference to the comparable section, if any, of
         any such similar federal statute.

                  "HOLDER": Profit Sharing and any other holder of Registrable
         Securities (including any direct or indirect transferees of Profit
         Sharing) who agrees in writing to be bound by the provisions of this
         Agreement.

                  "ORDINARY SHARES": The ordinary shares, par value $0.10 per
         share, of TA I Limited and its successors.

                  "ORDINARY SHARE OR ORDINARY SHARE EQUIVALENT REGISTRABLE
         SECURITIES": Registrable Securities which are (i) Ordinary Shares, (ii)
         ADSs representing Ordinary Shares or (iii) securities that are
         convertible into or exchangeable or exercisable for Ordinary Shares.

                  "OTHER HOLDERS": Any person that holds securities of the same
         Class as the Registrable Securities and has rights to have such
         securities registered under the Securities Act.

                  "PERSON": Any individual, partnership, joint venture,
         corporation, limited liability company, trust, unincorporated
         organization or government or any department or agency thereof.

                  "REGISTRABLE SECURITIES": Any Ordinary Shares acquired by
         Profit Sharing from the Company or any affiliate of the Company,
         including upon the conversion of any convertible security or otherwise,
         or ADSs representing any such Ordinary Shares and any Ordinary Shares,
         ADSs or convertible security which may be issued or distributed in
         respect thereof by way of stock dividend or stock split or other
         distribution, recapitalization or reclassification. As to any
         particular Registrable Securities, once issued, such Registrable
         Securities shall cease to be Registrable Securities when (i) a
         registration statement with respect to the sale by the Holder of such
         securities shall have become effective under the Securities Act and
         such securities shall have been disposed of in accordance with such
         registration statement, (ii) such securities shall have been
         distributed to the public pursuant to Rule 144 (or any successor
         provision) under the Securities Act, (iii) such securities shall have
         been otherwise transferred, new certificates for such securities not
         bearing a legend restricting further transfer shall have been delivered
         by the Company and subsequent disposition of such securities shall not
         require registration or qualification of such securities under the
         Securities Act or any state securities or blue sky law then in force,
         or (iv) such securities shall have ceased to be outstanding.

                  "REGISTRATION EXPENSES": Any and all expenses incident to
         performance of or compliance with this Agreement, including, without
         limitation, (i) all SEC and stock exchange or National Association of
         Securities Dealers, Inc. (the "NASD") registration and filing fees
         (including, if applicable, the fees and expenses of any "qualified
         independent underwriter," as such term is defined in Schedule E to the
         By-laws of the


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         NASD, and of its counsel), (ii) all fees and expenses of complying with
         securities or blue sky laws (including fees and disbursements of
         counsel for the underwriters in connection with blue sky qualifications
         of the Registrable Securities), (iii) all printing, messenger and
         delivery expenses, (iv) all fees and expenses incurred in connection
         with the listing of the Registrable Securities on any securities
         exchange pursuant to clause (viii) of Section 4, (v) the fees and
         disbursements of counsel for the Company and of its independent public
         accountants, including the expenses of any special audits and/or "cold
         comfort" letters required by or incident to such performance and
         compliance, (vi) the reasonable fees and disbursements of counsel
         selected pursuant to Section 7 hereof by the Holders of the Registrable
         Securities being registered to represent such Holders in connection
         with each such registration, (vii) any fees and disbursements of
         underwriters customarily paid by the issuers or sellers of securities,
         including liability insurance if the Company so desires or if the
         underwriters so require, and the reasonable fees and expenses of any
         special experts retained in connection with the requested registration,
         but excluding underwriting discounts and commissions and transfer
         taxes, if any, (viii) all fees and expenses incurred in connection with
         the creation of ADSs, including the reasonable fees and disbursements
         of the depositary for such ADSs that the Company, and not the
         depositary, is required to pay, and (ix) other reasonable out-of-pocket
         expenses of Holders (PROVIDED that such expenses shall not include
         expenses of counsel other than those provided for in clause (vi)
         above).

                  "SECURITIES ACT": The Securities Act of 1933, as amended, or
         any similar federal statute then in effect, and a reference to a
         particular section thereof shall be deemed to include a reference to
         the comparable section, if any, of any such similar federal statute.

                  "SEC": The Securities and Exchange Commission or any other
         federal agency at the time administering the Securities Act or the
         Exchange Act.

                  2. INCIDENTAL REGISTRATIONS. (a) RIGHT TO INCLUDE ORDINARY
SHARE OR ORDINARY SHARE EQUIVALENT REGISTRABLE SECURITIES. If the Company at any
time after the date hereof proposes to register its Ordinary Shares or ADSs
representing Ordinary Shares (or any security which is convertible into or
exchangeable or exercisable for Ordinary Shares) under the Securities Act (other
than a registration on Form F-4 or S-8, or any successor or other forms
promulgated for similar purposes), whether or not for sale for its own account,
in a manner which would permit registration of Ordinary Share or Ordinary Share
Equivalent Registrable Securities for sale to the public under the Securities
Act, it will, at each such time, give prompt written notice to all Holders of
Ordinary Share or Ordinary Share Equivalent Registrable Securities of its
intention to do so and of such Holders' rights under this Section 2. Upon the
written request of any such Holder made within 15 days after the receipt of any
such notice (which request shall specify the Ordinary Share or Ordinary Share
Equivalent Registrable Securities intended to be disposed of by such Holder),
the Company will use its best efforts to effect the registration under the
Securities Act of all Ordinary Share or Ordinary Share Equivalent Registrable
Securities which the Company has been so requested to register by the Holders
thereof, to the extent requisite to permit the disposition of the Ordinary Share
or Ordinary Share Equivalent Registrable Securities so to be registered;
PROVIDED that (i) if, at any time after giving written notice of its intention
to register any securities and prior to the effective


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date of the registration statement filed in connection with such registration,
the Company shall determine for any reason not to proceed with the proposed
registration of the securities to be sold by it, the Company may, at its
election, give written notice of such determination to each Holder of Ordinary
Share or Ordinary Share Equivalent Registrable Securities and, thereupon, shall
be relieved of its obligation to register any Ordinary Share or Ordinary Share
Equivalent Registrable Securities in connection with such registration (but not
from its obligation to pay the Registration Expenses in connection therewith),
and (ii) if such registration involves an underwritten offering, all Holders of
Ordinary Share or Ordinary Share Equivalent Registrable Securities requesting to
be included in the Company's registration must sell their Ordinary Share or
Ordinary Share Equivalent Registrable Securities to the underwriters selected by
the Company on the same terms and conditions as apply to the Company, with such
differences, including any with respect to indemnification and liability
insurance, as may be customary or appropriate in combined primary and secondary
offerings. If a registration requested pursuant to this Section 2(a) involves an
underwritten public offering, any Holder of Ordinary Share or Ordinary Share
Equivalent Registrable Securities requesting to be included in such registration
may elect, in writing prior to the effective date of the registration statement
filed in connection with such registration, not to register such securities in
connection with such registration. Nothing in this Section 2(a) shall operate to
limit the right of a Holder to (i) request the registration of Ordinary Shares
issuable upon conversion or exercise of convertible securities held by such
Holder notwithstanding the fact that at the time of request such Holder holds
only convertible securities or (ii) request the registration at one time of both
(A) Ordinary Shares or ADSs representing Ordinary Shares and (B) securities
convertible into Ordinary Shares.

                  (a) EXPENSES. The Company will pay all Registration Expenses
in connection with each registration of Ordinary Share or Ordinary Share
Equivalent Registrable Securities requested pursuant to this Section 2.

                  (b) PRIORITY IN INCIDENTAL REGISTRATIONS. If a registration
pursuant to this Section 2 involves an underwritten offering and the managing
underwriter advises the Company in writing that, in its opinion, the number of
securities requested to be included in such registration exceeds the number
which can be sold in such offering, so as to be likely to have an adverse effect
on the price, timing or distribution of the Securities offered in such offering
as contemplated by the Company, then the Company will include in such
registration (i) first, 100% of the securities the Company proposes to sell or,
in the case of a registration on request by a "Demand Party" pursuant to (and as
defined in) Section 3 of the Carrier Registration Rights Agreement, then, the
number of "Registrable Securities" of the requesting "Holders as contemplated by
(and as defined in) Section 3 of the Carrier Registration Rights Agreement, and,
in either event, (ii) second, the number of Ordinary Share or Ordinary Share
Equivalent Registrable Securities and securities of the same Class as the
Ordinary Share or Ordinary Share Equivalent Registrable Securities which the
Holders and Other Holders, as the case may be, have requested to be included in
such registration which, in the opinion of such managing underwriter, can be
sold without having the adverse effect referred to above, such amount to be
allocated pro rata among all requesting Holders and Other Holders on the basis
of the relative number of shares of Ordinary Share or Ordinary Share Equivalent
Registrable Securities and securities of such Class then held by each such
Holder and Other Holder (provided that any shares thereby allocated to


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any such Holder or Other Holder that exceed such Holder's or Other Holder's
request will be reallocated among the remaining requesting Holders and Other
Holders in like manner).

         3. REGISTRATION ON REQUEST. (a) REQUEST BY THE DEMAND PARTY. At any
time, upon the written request of the Demand Party requesting that the Company
effect the registration under the Securities Act of all or part of such Demand
Party's Registrable Securities and specifying the amount and intended method of
disposition thereof, the Company will promptly give written notice of such
requested registration to all other Holders of such Registrable Securities, and
thereupon will, as expeditiously as possible, use its best efforts to effect the
registration under the Securities Act of:

                  (i) such Registrable Securities (including, if such request
         relates to a security which is convertible into Ordinary Shares, the
         Ordinary Shares issuable upon such conversion) which the Company has
         been so requested to register by the Demand Party (and, if such request
         includes ADSs, the Ordinary Shares represented by such ADSs); and

                  (ii) all other Registrable Securities of the same Class and
         securities of such Class as are to be registered at the request of a
         Demand Party and which the Company has been requested to register by
         any other Holder and any Other Holder by written request given to the
         Company within 15 days after the giving of such written notice by the
         Company (which request shall specify the amount and intended method of
         disposition of such Registrable Securities and securities of such
         Class),

all to the extent necessary to permit the disposition (in accordance with the
intended method thereof as aforesaid) of the Registrable Securities and
securities of such Class so to be registered; PROVIDED, that with respect to any
Demand Party other than Profit Sharing, the Company shall not be obligated to
effect any registration of Registrable Securities under this Section 3(a) unless
such Demand Party requests that the Company register at least 1% of the total
number of Registrable Securities; and PROVIDED, FURTHER, that, unless Holders of
a majority of the shares of Registrable Securities held by Holders consent
thereto in writing, the Company shall not be obligated to file a registration
statement relating to any registration request under this Section 3(a) (x)
within a period of six months after the effective date of any other registration
statement relating to any registration request under this Section 3(a) which was
not effected on Form F-3 (or any successor or similar short-form registration
statement) or relating to any registration effected under Section 2, or (y) if
with respect thereto the managing underwriter, the SEC, the Securities Act or
the rules and regulations thereunder, or the form on which the registration
statement is to be filed, would require the conduct of an audit other than the
regular audit conducted by the Company at the end of its fiscal year, in which
case the filing may be delayed until the completion of such regular audit
(unless the Holders of the Registrable Securities and securities of such Class
to be registered agree to pay the expenses of the Company in connection with
such an audit other than the regular audit). Nothing in this Section 3 shall
operate to limit the right of a Holder to (i) request the registration of
Ordinary Shares issuable upon conversion or exercise of convertible securities
held by such Holder notwithstanding the fact that at the time of request such
Holder holds only convertible securities or (ii) request the registration at one
time of both Ordinary Shares or ADSs and securities convertible into Ordinary
Shares.


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         (b) REGISTRATION STATEMENT FORM. If any registration requested pursuant
to this Section 3 which is proposed by the Company to be effected by the filing
of a registration statement on Form F-3 (or any successor or similar short-form
registration statement) shall be in connection with an underwritten public
offering, and if the managing underwriter shall advise the Company in writing
that, in its opinion, the use of another form of registration statement is of
material importance to the success of such proposed offering, then such
registration shall be effected on such other form.

         (c) EXPENSES. The Company will pay all Registration Expenses in
connection with the first ten (10) registrations of each class or series of
Registrable Securities pursuant to this Section 3 upon the written request of
any of the Holders, PROVIDED that, for purposes hereof, a request to register
Ordinary Shares into which a convertible security is convertible in conjunction
with a registration of such convertible security shall be deemed to be one
request for registration of a class or series of Registrable Securities. All
expenses for any subsequent registrations of Registrable Securities pursuant to
this Section 3 shall be paid pro rata by the Company and all other Persons
(including the Holders) participating in such registration on the basis of the
relative number of Ordinary Shares of each such Person whose Registrable
Securities are included in such registration.

         (d) EFFECTIVE REGISTRATION STATEMENT. A registration requested pursuant
to this Section 3 will not be deemed to have been effected unless it has become
effective and all of the Registrable Securities registered thereunder have been
sold; PROVIDED that if, within 180 days after it has become effective, the
offering of Registrable Securities pursuant to such registration is interfered
with by any stop order, injunction or other order or requirement of the SEC or
other governmental agency or court, such registration will be deemed not to have
been effected.

         (e) SELECTION OF UNDERWRITERS. If a requested registration pursuant to
this Section 3 involves an underwritten offering, the Holders of a majority of
the shares of Registrable Securities which are held by Holders and which the
Company has been requested to register shall have the right to select the
investment banker or bankers and managers to administer the offering; PROVIDED,
HOWEVER, that such investment banker or bankers and managers shall be reasonably
satisfactory to the Company.

         (f) PRIORITY IN REQUESTED REGISTRATIONS. If a requested registration
pursuant to this Section 3 involves an underwritten offering and the managing
underwriter advises the Company in writing that, in its opinion, the number of
securities requested to be included in such registration (including securities
of the Company which are not Registrable Securities) exceeds the number which
can be sold in such offering without having an adverse effect, the Company will
include in such registration only the Registrable Securities and securities of
the same Class held by Other Holders requested to be included in such
registration. In the event that the number of Registrable Securities and
securities of the same Class held by Other Holders requested to be included in
such registration exceeds the number which, in the opinion of such managing
underwriter, can be sold, the number of such Registrable Securities and
securities of the same Class held by Other Holders to be included in such
registration shall be allocated pro rata among all requesting Holders and Other
Holders on the basis of the relative number of shares of


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Registrable Securities and securities of the same Class held by Other Holders
then held by each such Holder and Other Holder (provided that any shares thereby
allocated to any such Holder or Other Holder that exceed such Holder's or Other
Holder's request shall be reallocated among the remaining requesting Holders and
Other Holders in like manner). In the event that the number of Registrable
Securities and securities of the same Class held by Other Holders requested to
be included in such registration is less than the number which, in the opinion
of the managing underwriter, can be sold, the Company may include in such
registration the securities the Company proposes to sell up to the number of
securities that, in the opinion of the underwriter, can be sold without having
an adverse effect.

         (g) ADDITIONAL RIGHTS. If the Company at any time grants to any other
holders of Ordinary Shares any rights to request the Company to effect the
registration under the Securities Act of any such Ordinary Shares on terms more
favorable to such holders than the terms set forth in this Section 3, the terms
of this Section 3 shall be deemed amended or supplemented to the extent
necessary to provide the Holders such more favorable rights and benefits.

         4. REGISTRATION PROCEDURES. If and whenever the Company is required to
use its best efforts to effect or cause the registration of any Registrable
Securities under the Securities Act as provided in this Agreement, the Company
will, as expeditiously as possible:

                  (i) prepare and, in any event within 90 days after the end of
         the period within which a request for registration may be given to the
         Company, file and in the case of ADSs, cause to be filed with the SEC a
         registration statement or statements, if necessary, with respect to
         such Registrable Securities and use its best efforts to cause such
         registration statement or statements to become effective, PROVIDED,
         HOWEVER, that the Company may discontinue any registration of its
         securities which is being effected pursuant to Section 2 at any time
         prior to the effective date of the registration statement relating
         thereto;

                  (ii) prepare and file with the SEC such amendments and
         supplements to such registration statement or statements and the
         prospectus used in connection therewith as may be necessary to keep
         such registration statement or statements effective for a period not in
         excess of 270 days and to comply with the provisions of the Securities
         Act, the Exchange Act and the rules and regulations of the SEC
         thereunder with respect to the disposition of all securities covered by
         such registration statement during such period in accordance with the
         intended methods of disposition by the seller or sellers thereof set
         forth in such registration statement or statements; PROVIDED that
         before filing a registration statement or prospectus, or any amendments
         or supplements thereto, the Company will furnish to counsel selected
         pursuant to Section 7 hereof by the Holders of the Registrable
         Securities covered by such registration statement to represent such
         Holders, copies of all documents proposed to be filed, which documents
         will be subject to the review of such counsel;


                  (iii) furnish to each seller of such Registrable Securities
         such number of copies of such registration statement or statements and
         of each amendment and supplement thereto (in each case including all
         exhibits filed therewith, including any documents incorporated by
         reference), such number of copies of the prospectus included


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         in such registration statement or statements (including each
         preliminary prospectus and summary prospectus), in conformity with the
         requirements of the Securities Act, and such other documents as such
         seller may reasonably request in order to facilitate the disposition of
         the Registrable Securities by such seller;

                  (iv) use its best efforts to register or qualify such
         Registrable Securities covered by such registration in such
         jurisdictions as each seller shall reasonably request, and do any and
         all other acts and things which may be reasonably necessary or
         advisable to enable such seller to consummate the disposition in such
         jurisdictions of the Registrable Securities owned by such seller,
         except that the Company shall not for any such purpose be required to
         qualify generally to do business as a foreign corporation in any
         jurisdiction where, but for the requirements of this clause (iv), it
         would not be obligated to be so qualified, to subject itself to
         taxation in any such jurisdiction or to consent to general service of
         process in any such jurisdiction;

                  (v) use its best efforts to cause such Registrable Securities
         covered by such registration statement or statements to be registered
         with or approved by such other governmental agencies or authorities as
         may be necessary to enable the seller or sellers thereof to consummate
         the disposition of such Registrable Securities;

                  (vi) promptly notify each seller of any such Registrable
         Securities covered by such registration statement, at any time when a
         prospectus relating thereto is required to be delivered under the
         Securities Act within the appropriate period mentioned in clause (ii)
         of this Section 4, of the Company's becoming aware that the prospectus
         included in such registration statement, as then in effect, includes an
         untrue statement of a material fact or omits to state a material fact
         required to be stated therein or necessary to make the statements
         therein not misleading in the light of the circumstances then existing,
         and at the request of any such seller, promptly prepare and furnish to
         such seller a reasonable number of copies of an amended or supplemental
         prospectus as may be necessary so that, as thereafter delivered to the
         purchasers of such Registrable Securities, such prospectus shall not
         include an untrue statement of a material fact or omit to state a
         material fact required to be stated therein or necessary to make the
         statements therein not misleading in the light of the circumstances
         then existing;

                  (vii) otherwise use its best efforts to comply with all
         applicable rules and regulations of the SEC, and make available to its
         security holders, as soon as reasonably practicable (but not more than
         eighteen months) after the effective date of the registration
         statement, an earnings statement which shall satisfy the provisions of
         Section 11(a) of the Securities Act and the rules and regulations
         promulgated thereunder;

                  (viii) (A) if such Registrable Securities are Ordinary Shares
         or ADSs representing Ordinary Shares (including Ordinary Shares
         issuable upon conversion of a convertible security), use its best
         efforts to list such Registrable Securities on any securities exchange
         on which the Ordinary Shares or ADS representing Ordinary Shares are
         then listed if such Registrable Securities are not already so listed
         and if such listing is then permitted under the rules of such exchange;
         (B) if such Registrable Securities are


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         convertible securities, upon the reasonable request of sellers of a
         majority of shares of such Registrable Securities, use its best efforts
         to list the convertible securities and, if requested, the Ordinary
         Shares underlying the convertible securities, notwithstanding that at
         the time of request such sellers hold only convertible securities, on
         any securities exchange so requested, if such Registrable Securities
         are not already so listed, and if such listing is then permitted under
         the rules of such exchange; and (C) use its best efforts to provide a
         transfer agent and registrar for such Registrable Securities covered by
         such registration statement not later than the effective date of such
         registration statement;

                  (ix) enter into such customary agreements (including an
         underwriting agreement in customary form), which may include
         indemnification provisions in favor of underwriters and other persons
         in addition to, or in substitution for the provisions of Section 5
         hereof, and take such other actions as sellers of a majority of shares
         of such Registrable Securities or the underwriters, if any, reasonably
         requested in order to expedite or facilitate the disposition of such
         Registrable Securities;

                  (x) if requested by Holders of a majority of such Registrable
         Securities, enter into a deposit agreement in customary form for the
         creation of ADSs representing Ordinary Shares and take all other
         actions as Holders of a majority of such Registrable Securities
         reasonably requests in order to facilitate the creation and issuance of
         such ADSs; PROVIDED that after ADSs representing Ordinary Shares have
         been created, the Company shall only be required pursuant to this
         clause (x) to create additional ADSs representing the same number of
         Ordinary Shares per ADS as the ADSs that previously were created and
         issued;

                  (xi) obtain a "cold comfort" letter or letters from the
         Company's independent public accounts in customary form and covering
         matters of the type customarily covered by "cold comfort" letters as
         the seller or sellers of a majority of shares of such Registrable
         Securities shall reasonably request;

                  (xii) make available for inspection by any seller of such
         Registrable Securities covered by such registration statement or
         statements, by any underwriter participating in any disposition to be
         effected pursuant to such registration statement or statements, by any
         depositary with respect to Registrable Securities covered by such
         registration statement or statements and by any attorney, accountant or
         other agent retained by any such seller or any such underwriter or
         depositary, all pertinent financial and other records, pertinent
         corporate documents and properties of the Company, and cause all of the
         Company's officers, directors and employees to supply all information
         reasonably requested by any such seller, underwriter, attorney,
         accountant or agent in connection with such registration statement or
         statements;

                  (xiii) notify counsel (selected pursuant to Section 7 hereof)
         for the Holders of Registrable Securities included in such registration
         statement or statements and the managing underwriter or agent,
         immediately, and confirm the notice in writing (i) when the
         registration statement or statements, or any post-effective amendment
         thereto, shall have become effective, or any supplement to the
         prospectus or any amendment


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         prospectus shall have been filed, (ii) of the receipt of any comments
         from the SEC, (iii) of any request of the SEC to amend the registration
         statement or amend or supplement the prospectus or for additional
         information, and (iv) of the issuance by the SEC of any stop order
         suspending the effectiveness of the registration statement or
         statements or of any order preventing or suspending the use of any
         preliminary prospectus, or of the suspension of the qualification of
         the registration statement or statements for offering or sale in any
         jurisdiction, or of the institution or threatening of any proceedings
         for any of such purposes;

                  (xiv) make every reasonable effort to prevent the issuance of
         any stop order suspending the effectiveness of the registration
         statement or statements or of any order preventing or suspending the
         use of any preliminary prospectus and, if any such order is issued, to
         obtain the withdrawal of any such order at the earliest possible
         moment;

                  (xv) if requested by the managing underwriter or agent or any
         Holder of Registrable Securities covered by the registration statement
         or statements, promptly incorporate and, in the case of ADSs, promptly
         cause to be incorporated in a prospectus supplement or post-effective
         amendment such information as the managing underwriter or agent or such
         Holder reasonably requests to be included therein, including, without
         limitation, with respect to the number of Registrable Securities being
         sold by such Holder to such underwriter or agent, the purchase price
         being paid therefor by such underwriter or agent and with respect to
         any other terms of the underwritten offering of the Registrable
         Securities to be sold in such offering; and make and, in the case of
         ADSs, cause to be made all required filings of such prospectus
         supplement or post-effective amendment as soon as practicable after
         being notified of the matters incorporated in such prospectus
         supplement or post-effective amendment;

                  (xvi) cooperate with the Holders of Registrable Securities
         covered by such registration statement or statements and the managing
         underwriter or agent or depositary, if any, to facilitate the timely
         preparation and delivery of certificates (not bearing any restrictive
         legends) representing the securities to be sold under the registration
         statement or statements, and enable such securities to be in such
         denominations and registered in such names as the managing underwriter
         or agent, if any, or such Holders may request;

                  (xvii) obtain for delivery to the Holders of Registrable
         Securities being registered and to the underwriter or agent or
         depositary an opinion or opinions from counsel for the Company in
         customary form and in form, substance and scope reasonably satisfactory
         to such Holders, underwriters or agents or depositary and their
         counsel; and

                  (xviii) cooperate with each seller of Registrable Securities
         and each underwriter or agent participating in the disposition of such
         Registrable Securities and their respective counsel in connection with
         any filings required to be made with the NASD.


                                       10

<PAGE>


         The Company may require each seller of Registrable Securities as to
which any registration is being effected to furnish the Company with such
information regarding such seller and pertinent to the disclosure requirements
relating to the registration and the distribution of such securities as the
Company may from time to time reasonably request in writing.

         Each Holder of Registrable Securities agrees that, upon receipt of any
notice from the Company of the happening of any event of the kind described in
clause (vi) of this Section 4, such Holder will forthwith discontinue
disposition of Registrable Securities pursuant to the registration statement
covering such Registrable Securities until such Holder's receipt of the copies
of the supplemented or amended prospectus contemplated by clause (vi) of this
Section 4, and, if so directed by the Company, such Holder will deliver to the
Company (at the Company's expense) all copies, other than permanent file copies
then in such Holder's possession, of the prospectus covering such Registrable
Securities current at the time of receipt of such notice. In the event the
Company shall give any such notice, the period mentioned in clause (ii) of this
Section 4 shall be extended by the number of days during the period from and
including the date of the giving of such notice pursuant to clause (vi) of this
Section 4 and including the date when each seller of Registrable Securities
covered by such registration statement shall have received the copies of the
supplemented or amended prospectus contemplated by clause (vi) of this Section
4.

         5. INDEMNIFICATION. (a) INDEMNIFICATION BY THE COMPANY. In the event of
any registration of any securities of the Company under the Securities Act
pursuant to Section 2 or 3, the Company will, and it hereby does, indemnify and
hold harmless, to the extent permitted by law, the seller of any Registrable
Securities covered by any such registration statement, each affiliate of such
seller and their respective directors and officers or general and limited
partners or members or managing members (including any director, officer,
affiliate, employee, agent and controlling Person of any of the foregoing), each
other Person who participates as an underwriter in the offering or sale of such
securities and each other Person, if any, who controls such seller or any such
underwriter within the meaning of the Securities Act (collectively, the
"INDEMNIFIED PARTIES"), against any and all losses, claims, damages or
liabilities, joint or several, and expenses (including reasonable attorney's
fees and reasonable expenses of investigation) to which such Indemnified Party
may become subject under the Securities Act, common law or otherwise, insofar as
such losses, claims, damages or liabilities (or actions or proceedings in
respect thereof, whether or not such Indemnified Party is a party thereto) arise
out of or are based upon (a) any untrue statement or alleged untrue statement of
any material fact contained in any registration statement under which such
securities were registered under the Securities Act, any preliminary, final or
summary prospectus contained therein, or any amendment or supplement thereto, or
(b) any omission or alleged omission to state therein a material fact required
to be stated therein or necessary to make the statements therein (in the case of
a prospectus, in light of the circumstances under which they were made) not
misleading, and the Company will reimburse such Indemnified Party for any legal
or any other expenses reasonably incurred by it in connection with investigating
or defending against any such loss, claim, liability, action or proceeding;
PROVIDED that the Company shall not be liable to any Indemnified Party in any
such case to the extent that any such loss, claim, damage, liability (or action
or proceeding in respect thereof) or expense arises out of or is based upon any
untrue statement or alleged untrue statement or omission or alleged omission
made in such registration statement or amendment or

                                       11

<PAGE>

supplement thereto or in any such preliminary, final or summary prospectus in
reliance upon and in conformity with written information furnished to the
Company through an instrument duly executed by such seller specifically stating
that it is for use in the preparation thereof. Such indemnity shall remain in
full force and effect regardless of any investigation made by or on behalf of
such seller or any Indemnified Party and shall survive the transfer of such
securities by such seller.

         (a) INDEMNIFICATION BY THE SELLER. The Company may require, as a
condition to including any Registrable Securities in any registration statement
filed in accordance with Section 4 herein, that the Company shall have received
an undertaking reasonably satisfactory to it from the prospective seller of such
Registrable Securities or any underwriter to indemnify and hold harmless (in the
same manner and to the same extent as set forth in subdivision (a) of this
Section 5) the Company and all other prospective sellers with respect to any
untrue statement or alleged untrue statement in or omission or alleged omission
from such registration statement, any preliminary, final or summary prospectus
contained therein, or any amendment or supplement, if such untrue statement or
alleged untrue statement or omission or alleged omission was made in reliance
upon and in conformity with written information furnished to the Company through
an instrument duly executed by such seller or underwriter specifically stating
that it is for use in the preparation of such registration statement,
preliminary, final or summary prospectus or amendment or supplement, or a
document incorporated by reference into any of the foregoing. Such indemnity
shall remain in full force and effect regardless of any investigation made by or
on behalf of the Company or any of the prospective sellers, or any of their
respective affiliates, directors, officers or controlling Persons and shall
survive the transfer of such securities by such seller. In no event shall the
liability of any selling Holder of Registrable Securities hereunder be greater
in amount than the dollar amount of the proceeds received by such Holder upon
the sale of the Registrable Securities giving rise to such indemnification
obligation.

         (b) NOTICES OF CLAIMS, ETC. Promptly after receipt by an Indemnified
Party hereunder of written notice of the commencement of any action or
proceeding with respect to which a claim for indemnification may be made
pursuant to this Section 5, such Indemnified Party will, if a claim in respect
thereof is to be made against an indemnifying party, give written notice to the
latter of the commencement of such action; PROVIDED that the failure of the
Indemnified Party to give notice as provided herein shall not relieve the
indemnifying party of its obligations under the preceding subdivisions of this
Section 5, except to the extent that the indemnifying party is actually
prejudiced by such failure to give notice. In case any such action is brought
against an Indemnified Party, unless in such Indemnified Party's reasonable
judgment a conflict of interest between such Indemnified Party and indemnifying
parties may exist in respect of such claim, the indemnifying party will be
entitled to participate in and to assume the defense thereof, jointly with any
other indemnifying party similarly notified to the extent that it may wish, with
counsel reasonably satisfactory to such Indemnified Party, and after notice from
the indemnifying party to such Indemnified Party of its election so to assume
the defense thereof, the indemnifying party will not be liable to such
Indemnified Party for any legal or other expenses subsequently incurred by the
latter in connection with the defense thereof other than reasonable costs of
investigation. No indemnifying party will consent to entry of any judgment or
enter into any settlement which does not include as an unconditional term
thereof, the giving

                                       12

<PAGE>

by the claimant or plaintiff to such Indemnified Party of a release from all
liability in respect to such claim or litigation.

         (d) CONTRIBUTION. If the indemnification provided for in this Section 5
from the indemnifying party is unavailable to an Indemnified Party hereunder in
respect of any losses, claims, damages, liabilities or expenses referred to
herein, then the indemnifying party, in lieu of indemnifying such Indemnified
Party, shall contribute to the amount paid or payable by such Indemnified Party
as a result of such losses, claims, damages, liabilities or expenses in such
proportion as is appropriate to reflect the relative fault of the indemnifying
party and Indemnified Parties in connection with the actions which resulted in
such losses, claims, damages, liabilities or expenses, as well as any other
relevant equitable considerations. The relative fault of such indemnifying party
and Indemnified Parties shall be determined by reference to, among other things,
whether any action in question, including any untrue or alleged untrue statement
of a material fact or omission or alleged omission to state a material fact, has
been made by, or relates to information supplied by, such indemnifying party or
Indemnified Parties, and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such action. The amount paid
or payable by a party under this Section 5(d) as a result of the losses, claims,
damages, liabilities and expenses referred to above shall be deemed to include
any legal or other fees or expenses reasonably incurred by such party in
connection with any investigation or proceeding.

         The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 5(d) were determined by pro rata
allocation or by any other method of allocation which does not take account of
the equitable considerations referred to in the immediately preceding paragraph.
No Person guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the Securities Act) shall be entitled to contribution from any Person
who was not guilty of such fraudulent misrepresentation.

         (e) OTHER INDEMNIFICATION. Indemnification similar to that specified in
the preceding subdivisions of this Section 5 (with appropriate modifications)
shall be given by the Company and each seller of Registrable Securities with
respect to any required registration or other qualification of securities under
any federal or state law or regulation or governmental authority other than the
Securities Act.

         (f) NON-EXCLUSIVITY. The obligations of the parties under this Section
5 shall be in addition to any liability which any party may otherwise have to
any other party.

         6. RULE 144. The Company covenants that it will file the reports
required to be filed by it under the Securities Act and the Exchange Act and the
rules and regulations adopted by the SEC thereunder (or, if the Company is not
required to file such reports, it will, upon the request of any Holder of
Registrable Securities, make publicly available such information), and it will
take such further action as any Holder of Registrable Securities may reasonably
request, all to the extent required from time to time to enable such Holder to
sell shares of Registrable Securities without registration under the Securities
Act within the limitation of the exemptions provided by (i) Rule 144 under the
Securities Act, as such Rule may be amended from time to time, or (ii) any
similar rule or regulation hereafter adopted by the SEC. Upon the request of any


                                       13

<PAGE>

Holder of Registrable Securities, the Company will deliver to such Holder a
written statement as to whether it has complied with such requirements.
Notwithstanding anything contained in this Section 6, the Company may
de-register under Section 12 of the Exchange Act if it then is permitted to do
so pursuant to the Exchange Act and the rules and regulations thereunder and, in
such circumstances, shall not be required hereby to file any reports which may
be necessary in order for Rule 144 or any similar rule or regulation to be
available.

         7. SELECTION OF COUNSEL. In connection with any registration of
Registrable Securities pursuant to Sections 2 and 3 hereof, the Holders of a
majority of the Registrable Securities covered by any such registration may
select one U.S. counsel to represent all Holders of Registrable Securities
covered by such registration, and to the extent necessary, one U.K. counsel;
PROVIDED, HOWEVER, that in the event that any counsel selected as provided above
is also acting as counsel to the Company in connection with such registration,
the remaining Holders shall be entitled to select one additional U.S. or U.K.
counsel, as applicable, to represent all such remaining Holders.

         8. MISCELLANEOUS. (a) OTHER INVESTORS. The Company may enter into
agreements with other holders and purchasers of Ordinary Shares who are then
employees of the Company (or its successor) or any of its subsidiaries, making
them parties hereto (and thereby giving them all, or a portion, of the rights,
preferences and privileges of an original party hereto) with respect to
additional Ordinary Shares (the "SUPPLEMENTAL AGREEMENTS"); provided, however,
that pursuant to any such Supplemental Agreement, such holder or purchaser
expressly agrees to be bound by all of the terms, conditions and obligations of
this Agreement as if such holder or purchaser were an original party hereto. All
Ordinary Shares issued or issuable pursuant to such Supplemental Agreements
shall be deemed to be Registrable Securities.

         (a) HOLDBACK AGREEMENT. If any such registration shall be in connection
with an underwritten public offering, each Holder of Registrable Securities
agrees not to effect any public sale or distribution, including any sale
pursuant to Rule 144 under the Securities Act, of any equity securities of the
Company, or of any security convertible into or exchangeable or exercisable for
any equity security of the Company (in each case, other than as part of such
underwritten public offering), within 7 days before or such period not to exceed
60 days as the underwriting agreement may require (or such lesser period as the
managing underwriters may permit) after the effective date of such registration
(except as part of such registration), and the Company hereby also so agrees and
agrees to cause each other holder of any equity security, or of any security
convertible into or exchangeable or exercisable for any equity security, of the
Company purchased from the Company (at any time other than in a public offering)
to so agree. This Section 8(b) is in addition to, and shall not be deemed to be
in limitation of, the obligations which any party to a Management and Employee
Stockholders' and Subscription Agreement with the Company may have under
Section3(e) thereof.

         (b) AMENDMENTS AND WAIVERS. This Agreement may be amended and the
Company may take any action herein prohibited, or omit to perform any act herein
required to be performed by it, only if the Company shall have obtained the
written consent to such amendment, action or omission to act, of the Holders of
a majority of the Registrable Securities then outstanding; PROVIDED, HOWEVER,
that no amendment, waiver or consent to the departure


                                       14

<PAGE>

from the terms and provisions of this Agreement that is adverse to Profit
Sharing or any of its respective successors and assigns shall be effective as
against any such Person for so long as such Person holds any Registrable
Securities unless consented to in writing by such Person. Each Holder of any
Registrable Securities at the time or thereafter outstanding shall be bound by
any consent authorized by this Section 8(c), whether or not such Registrable
Securities shall have been marked to indicate such consent.

         (c) SUCCESSORS, ASSIGNS AND TRANSFEREES. This Agreement shall be
binding upon and shall inure to the benefit of the parties hereto and their
respective successors and assigns. In addition, and whether or not any express
assignment shall have been made, the provisions of this Agreement which are for
the benefit of the parties hereto other than the Company shall also be for the
benefit of and enforceable by any subsequent Holder of any Registrable
Securities, subject to the provisions contained herein. Without limitation to
the foregoing, in the event that Profit Sharing distributes or otherwise
transfers any shares of the Registrable Securities to any of its present or
future general or limited partners, the Company hereby acknowledges that the
registration rights granted pursuant to this Agreement shall be transferred to
such partner or partners on a pro rata basis, and that at or after the time of
any such distribution or transfer, any such partner or group of partners may
designate a Person to act on its behalf in delivering any notices or making any
requests hereunder.

         (d) NOTICES. All notices and other communications provided for
hereunder shall be in writing and shall be sent by first class mail, telex,
telecopier or hand delivery:

                  (i) (A) if to the Company, to:

                  TA I Limited
                  c/o Kohlberg Kravis Roberts & Co.
                  9 West 57th Street
                  Suite 4200
                  New York, New York 10019
                  Attention: Perry Golkin

                  (ii) if to Profit Sharing, to:


                                       15

<PAGE>


                  c/o Kohlberg Kravis Roberts & Co.
                  9 West 57th Street
                  Suite 4200
                  New York, New York 10019
                  Attention: Perry Golkin

                  with a copy to:

                  Simpson Thacher & Bartlett
                  99 Bishopsgate
                  21st Floor
                  London EC2M 3YH
                  Attention:  Gregory W. Conway, Esq

                  and:

                  Clifford Chance
                  200 Aldersgate Street
                  London  EC1A 4JJ
                  Attention:  Daniel Kossoff and Robin Tremaine

                  (iii) if to any other holder of Registrable Securities, to the
         address of such other holder as shown in the stock record book of the
         Company, or to such other address as any of the above shall have
         designated in writing to all of the other above.

         All such notices and communications shall be deemed to have been given
or made (1) when delivered by hand, (2) five business days after being deposited
in the mail, postage prepaid, (3) when telexed answer-back received or (4) when
telecopied, receipt acknowledged.

         (e) DESCRIPTIVE HEADINGS. The headings in this Agreement are for
convenience of reference only and shall not limit or otherwise affect the
meaning of terms contained herein.

         (f) SEVERABILITY. In the event that any one or more of the provisions,
paragraphs, words, clauses, phrases or sentences contained herein, or the
application thereof in any circumstances, is held invalid, illegal or
unenforceable in any respect for any reason, the validity, legality and
enforceability of any such provision, paragraph, word, clause, phrase or
sentence in every other respect and of the remaining provisions, paragraphs,
words, clauses, phrases or sentences hereof shall not be in any way impaired, it
being intended that all rights, powers and privileges of the parties hereto
shall be enforceable to the fullest extent permitted by law.

         (g) COUNTERPARTS. This Agreement may be executed in counterparts, and
by different parties on separate counterparts, each of which shall be deemed an
original, but all such counterparts shall together constitute one and the same
instrument.

                                       16

<PAGE>


         (h) GOVERNING LAW; SUBMISSION TO JURISDICTION. This Agreement shall be
governed by and construed and enforced in accordance with the laws of the State
of New York applicable to contracts made and to be performed therein. The
parties to this Agreement hereby agree to submit to the jurisdiction of the
courts of the State of New York, the courts of the United States of America for
the Southern District of New York, and appellate courts from any thereof in any
action or proceeding arising out of or relating to this Agreement.

         (i) SPECIFIC PERFORMANCE. The parties hereto acknowledge and agree that
irreparable damage would occur in the event that any of the provisions of this
Agreement were not performed in accordance with their specific terms or were
otherwise breached. Accordingly, it is agreed that they shall be entitled to an
injunction or injunctions to prevent breaches of the provision of this Agreement
and to enforce specifically the terms and provisions hereof in any court of
competent jurisdiction in the United States or any state thereof, in addition to
any other remedy to which they may be entitled at law or in equity.

         (j) LIMITED LIABILITY OF PARTNERS. Notwithstanding any other provision
of this Agreement, neither the general partner nor any future general of Profit
Sharing shall have any personal liability for performance of any obligation of
Profit Sharing under this Agreement.


                                       17

<PAGE>


                  IN WITNESS WHEREOF, each of the undersigned has executed this
Agreement or caused this Agreement to be duly executed on its behalf as of the
date first written above.

                               PROFIT SHARING (OVERSEAS), LIMITED
                               PARTNERSHIP

                                   By:  KKR 1996 Fund (Overseas), Limited
                                            Partnership, as its general partner

                                   By:  KKR Associates II (1996), Limited
                                            Partnership, its General Partner

                                   By:  KKR 1996 Overseas Limited,
                                            its general partner

                                   By: /s/ Perry Golkin
                                       ----------------------------------
                                       Authorized Signatory


                               TA I LIMITED

                                   By: /s/ Scott Nuttal
                                       ----------------------------------
                                   Authorized Signatory


                                       18