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                                                                     Exhibit 4.2

                           CERTIFICATE OF DESIGNATIONS

                                       OF

               2.0% CUMULATIVE SENIOR CONVERTIBLE PREFERRED SHARES

          The terms of the authorized 2.0% Cumulative Senior Convertible
Preferred Shares, par value $0.10 per share (the "Senior Preferred Shares") of
Global Crossing Limited (formerly GC Acquisition Ltd.), a company incorporated
under the laws of Bermuda (the "Company"), shall be as set forth below in this
Schedule to the Bye-laws of the Company (this "Schedule").

          The Senior Preferred Shares have been purchased pursuant to a Purchase
Agreement dated as of August 9, 2002 among Global Crossing Ltd., Global Crossing
Holdings Ltd., Singapore Technologies Telemedia Pte Ltd. ("STT") and others, as
amended.

          Certain terms are defined in Section 12 of this Schedule. Unless
otherwise provided herein, all Section references in this Schedule refer to
Sections of this Schedule. Capitalized terms used but not otherwise defined in
this Schedule have the meanings set forth in the Bye-laws of the Company.

     1.   Designations. There are hereby authorized 45,000,000 Senior Preferred
Shares as designated by the Board. Each Senior Preferred Share will have a
liquidation preference of $10.00 (the "Liquidation Preference").

     2.   Currency. All Senior Preferred Shares shall be denominated in United
States currency, and all payments and distributions thereon or with respect
thereto shall be made in United States currency. All references herein to "$" or
"dollars" refer to United States currency.

     3.   Ranking.

          3.1.   Subject to Section 4.7 and Section 5.3, the Senior Preferred
Shares shall, with respect to dividend rights and rights upon liquidation or
winding up, rank senior to all other classes or series of shares in the share
capital of the Company, including, without limitation, the Common Shares and
other Equity Securities. All Equity Securities to which the Senior Preferred
Shares ranks prior (whether with respect to dividends or upon liquidation,
winding up or otherwise), including the Common Shares, are collectively referred
to herein as the "Junior Shares." The definition of Junior Shares shall also
include any warrants, rights, calls or options exercisable for or convertible
into any Junior Shares.

          3.2.   The Company shall not issue any Equity Securities which rank
senior to, or pari passu with, the Senior Preferred Shares with respect to any
rights; provided, however, nothing in this Section 3.2 shall prohibit the
Company from issuing any Common Shares or other Equity Securities that are
entitled to vote, in person or by proxy, at a special or annual meeting of
shareholders or in any written consent in lieu of meeting, on all matters
entitled to be voted on by holders of Common Shares voting together as a single
class with the Common Shares (and with other shares entitled to vote thereon, if
any).

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     4.   Dividends.

          4.1.   The holders of Senior Preferred Shares shall only be entitled
to receive payment of dividends on the Senior Preferred Shares, to the extent
provided in this Section 4, after the Company and its Subsidiaries have, on a
consolidated basis (excluding Global Marine and its subsidiaries) and according
to the audited consolidated accounts of the Company (prepared in accordance with
U.S. Generally Accepted Accounting Principals consistently applied), achieved
cumulative operating earnings before interest, taxes, depreciation and
amortization (but excluding the contribution of (i) any revenue recognized
immediately for circuit activations that qualified as sales-type leases, (ii)
revenue recognized due to the amortisation of indefeasible rights of use sold in
prior periods and not recognized as sales-type leases, and (iii) revenue
recognized from extra-ordinary transactions or from the disposition of assets of
the Company or any Subsidiary other than in the ordinary course of business) of
$650,000,000 or more.

          4.2.   The holders of Senior Preferred Shares shall be entitled to
receive, when, as and if declared by the Board out of funds legally available
therefor, dividends on the Senior Preferred Shares, cumulative from their date
of issue, at a rate per annum of 2.0% of the Liquidation Preference per share,
payable in cash. Subject to Section 4.1, dividends on the Senior Preferred
Shares shall be payable with respect to each quarterly period ending on the last
day of March, June, September and December (each such period, a "Dividend
Period") and in equal amounts (subject to Section 4.6 hereunder with respect to
shorter periods, including the first such period with respect to which dividends
are payable) in arrears on the fifteenth day of each April, July, October and
January of each year, or if any such date is not a Business Day, on the next
succeeding Business Day (each such date, a "Dividend Payment Date") in
preference to and in priority over dividends on any Junior Shares, other than
distributions to shareholders provided for under Section 5.3, which shall be
made pro rata to Shareholders as provided herein. Such dividends shall be paid
to the holders of record of the Senior Preferred Shares as they appear on the
applicable Record Date. As used herein, the term "Record Date", with respect to
the dividends payable on the fifteenth of April, July, October and January,
means the last day of the immediately preceding February, May, August and
November, respectively, or such other record date, not more than 60 days and not
less than 10 days preceding the applicable Dividend Payment Date, as shall be
fixed by the Board. Dividends on the Senior Preferred Shares shall be fully
cumulative and shall accrue (whether or not declared and whether or not there
are funds of the Company legally available for the payment of dividends) from
their date of issue (or the last Record Date for which dividends were paid, as
the case may be). Accrued and unpaid dividends for any past Dividend Period may
be declared and paid at any time, without reference to any Dividend Payment
Date, to holders of record on such date, not more than 45 days prior to the
payment thereof, as may be fixed by the Board. Notwithstanding anything to the
contrary in the foregoing, any distributions made to the holders of Senior
Preferred Shares under Section 5.3 shall offset, dollar for dollar, any
dividends due to the holders of the Senior Preferred Shares under this Section
4.2.

          4.3.   Subject to Section 5.3, no dividend shall be declared or paid
or set apart for payment, or other distribution declared or made, whether in
cash, obligations or shares of the Company or other property, directly or
indirectly, upon any Junior Shares, nor shall any Junior Shares be redeemed,
repurchased or otherwise acquired for consideration by the Company through a
sinking fund or otherwise, other than Common Shares redeemed or repurchased
pursuant to the terms of the Share Option Plan, unless all accrued and unpaid

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dividends through the most recent Dividend Payment Date (whether or not such
dividends have been declared and whether or not there are funds of the Company
legally available for the payment of dividends) on the Senior Preferred Shares
have been or contemporaneously are declared and paid in full.

          4.4.   Any dividend payment made on the Senior Preferred Shares shall
first be credited against the dividends accrued with respect to the earliest
Dividend Period for which dividends have not been paid.

          4.5.   All dividends paid with respect to Senior Preferred Shares
pursuant to this Section 4 shall be paid pro rata to the holders entitled
thereto based upon the number of Senior Preferred Shares held by each.

          4.6.   Dividends (or cash amounts equal to accrued and unpaid
dividends) payable on the Senior Preferred Shares for any period shorter than
three months shall be computed on the basis of the actual number of days elapsed
either (x) from the date of issue of the Senior Preferred Shares to the last day
of the Dividend Period within which such date falls, or (y) from the
commencement of the Dividend Period in which the Senior Preferred Shares are
converted to the day immediately preceding the date of delivery of the Senior
Preferred Shares for conversion, as applicable. No interest shall accrue or be
payable in respect of any accumulation of dividends or unpaid dividends on the
Senior Preferred Shares.

          4.7.   After payment in full of the accumulated and unpaid dividends
to which holders of Senior Preferred Shares are entitled, any further dividends
paid by the Company to its Shareholders shall be distributed, first amongst the
holders of the Common Shares on a pro rata basis, until the Company has paid in
respect of each Common Share an amount equal to the aggregate amount of
dividends paid per Senior Preferred Share, and second amongst the holders of the
Senior Preferred Shares and the holders of the Common Shares on a pro rata
basis, in each case assuming each holder of Senior Preferred Shares had
converted its Senior Preferred Shares into Common Shares pursuant to Section 8
below on the date of distribution by the Company.

     5.   Liquidation Preference.

          5.1.   Except as provided in Section 5.3, upon any voluntary or
involuntary liquidation, dissolution or winding up of the Company or a reduction
or decrease in the Company's share capital resulting in a distribution of assets
to the holders of any class or series of the Company's share capital, each
holder of Senior Preferred Shares shall be entitled to payment out of the assets
of the Company available for distribution of an amount equal to the Liquidation
Preference per Senior Preferred Share held by such holder, plus all accumulated
and unpaid dividends therein to the date of such liquidation, dissolution,
winding up or reduction or decrease in share capital before any distribution is
made on any Junior Shares. After payment in full of the Liquidation Preference
and all accumulated and unpaid dividends to which holders of Senior Preferred
Shares are entitled, any further distribution made by the Company to its
Shareholders shall be distributed, first amongst the holders of the Common
Shares on a pro rata basis, until the Company has made a distribution to each
Common Share equal to the Liquidation Preference per Senior Preferred Share
divided by the Conversion Ratio, and second amongst the holders of the Senior
Preferred Shares and the holders of the Common Shares on a pro rata basis,
assuming each holder of Senior Preferred Shares had converted its Senior
Preferred Shares into Common Shares pursuant to Section 8 below on the date of
distribution by the Company.

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          5.2.   Neither the voluntary sale, conveyance, exchange or transfer
(for cash, shares of stock, securities or other consideration) of all or
substantially all of the property or assets of the Company nor the
consolidation, merger or amalgamation of the Company with or into any
corporation or the consolidation, merger or amalgamation of any corporation with
or into the Company shall be deemed to be a voluntary or involuntary
liquidation, dissolution or winding up of the Company or a reduction or decrease
in the share capital of the Company, unless the consolidation, merger or
amalgamation is undertaken for the purpose of reducing or decreasing the share
capital of the Company.

          5.3.   Any distribution made by the Company to its Shareholders
resulting from a sale of all or any part of the assets of the Company or any of
its Subsidiaries shall be distributed amongst the holders of the Senior
Preferred Shares and the holders of the Common Shares on a pro rata basis,
assuming each holder of Senior Preferred Shares had converted its Senior
Preferred Shares into Common Shares pursuant to Section 8 below on the date of
distribution by the Company. For the avoidance of doubt, (i) Section 4.1 shall
not apply to distributions to holders of Senior Preferred Shares under this
Section 5.3, and, subject to the last sentence of Section 4.2, the holders of
Senior Preferred Shares shall be entitled to receive such distributions without
reference to the $650,000,000 cumulative operating earnings threshold specified
in Section 4.1, (ii) payment of dividends to holders of Senior Preferred Shares
in preference to and in priority over dividends payable on Junior Shares
pursuant to Section 4.2 shall not apply to distributions made under this Section
5.3, and (iii) Section 4.7 shall not apply to distributions made under this
Section 5.3.

     6.   No Redemption. Senior Preferred Shares shall not be redeemable.

     7.   Voting Rights.

          7.1.   In addition to the voting rights to which the holders of Senior
Preferred Shares are entitled under or granted by Bermuda law, the holders of
Senior Preferred Shares shall be entitled to vote, in person or by proxy, at a
special or annual meeting of shareholders or in any written consent in lieu of
meeting, on all matters entitled to be voted on by holders of Common Shares
voting together as a single class with the Common Shares (and with other shares
entitled to vote thereon, if any). With respect to any such vote, each Senior
Preferred Share shall entitle the holder thereof to cast that number of votes as
is equal to the number of votes that such holder would be entitled to cast had
such holder converted its Senior Preferred Shares into Common Shares pursuant to
Section 8 below on the record date for determining the shareholders of the
Company eligible to vote on any such matters.

          7.2.   For so long as the holders of the Senior Preferred Shares
continue to own the Relevant Percentage, the special rights attaching to the
Senior Preferred Shares shall, with the intent that this Section 7.2 shall
create rights attaching to the Senior Preferred Shares for the purposes of
section 47 of the Companies Acts, be deemed to be varied by any of the following
actions with respect to the Company or any of its Subsidiaries, and the prior
consent or sanction of the holders of the Senior Preferred Shares (given in
accordance with Bye-law 7) shall be required for every such action and the
Company shall not permit any of them to be carried out, and shall take all
actions within its power to prevent any of its Subsidiaries from carrying any of
them out, without such consent or sanction:

                 (a)  appoint, or replace from office, the Chief Executive
Officer of the Company;

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                 (b)  enter into, or vary the material terms of, any transaction
or series of related transactions involving the acquisition or disposition of
assets for aggregate consideration in excess of $25,000,000, other than
transactions between the Company and any wholly-owned Subsidiary of the Company
or between wholly-owned Subsidiaries of the Company;

                 (c)  enter into any merger, amalgamation or consolidation with
any other entity or any reorganization or recapitalization of its share capital,
other than any such transaction not involving any person other than the Company
and wholly-owned Subsidiaries of the Company;

                 (d)  issue, redeem or repurchase any Equity Securities, other
than (i) the issuance of stock options (and Common Shares issuable pursuant to
the exercise of stock options) granted, or the award of Commons Shares, under
the Share Option Plan, (ii) the repurchase of Common Shares under the vesting
provisions of any such options or awards, (iii) the issuance of shares of any
Subsidiary of the Company to the Company or to any other wholly-owned Subsidiary
of the Company, (iv) the issuance of Senior Preferred Shares in connection with
adjustments provided for in Section 9 or (v) the issuance of Common Shares upon
conversion of Senior Preferred Shares;

                 (e)  incur or guarantee any indebtedness (including without
limitation through the issuance of any bonds, notes or other financial
obligations) other than (i) indebtedness and guarantees existing on the date of
issuance of the Senior Preferred Shares, (ii) trade indebtedness incurred in the
ordinary course of business and (iii) consolidated indebtedness of the Company
and its Subsidiaries in an aggregate amount not to exceed $25,000,000 incurred
in any calendar year;

                 (f)  incur any single capital expenditure (or group of related
capital expenditures to the extent each forms a part of one cohesive project) in
excess of $25,000,000 annually and any other expenditures in excess of
$25,000,000 not included in the operating budget approved by the Board;

                 (g)  (1) commence any case, proceeding or other action (A)
under any bankruptcy, insolvency or similar law seeking to have an order of
relief entered with respect to it or seeking to adjudicate it a bankrupt or
insolvent, or seeking reorganization, arrangement, adjustment, winding up,
liquidation, dissolution, composition or other relief with respect to it or its
debts or (B) to seek appointment of a receiver, trustee, custodian or other
similar official for it or all or any substantial part of its property, (2) make
a general assignment for the benefit of its creditors or (3) admit in writing
its inability to pay its debts when they become due;

                 (h)  enter into, or vary the material terms of, any transaction
with any Related Party or its Subsidiaries, provided that this restriction shall
not apply to (1) transactions entered into before the Relevant Date or otherwise
expressly contemplated by the Plan of Reorganization of Global Crossing Ltd. and
certain of its Subsidiaries approved by the United States Bankruptcy Court for
the Southern District of New York on September 16, 2002, as amended from time to
time, (2) transactions entered into after the Relevant Date between the Company
or any of its Subsidiaries on the one hand and the STT Group Parent or any
Subsidiary of the STT Group Parent on the other hand, and (3) transactions
entered into after the Relevant Date which are entered into in the ordinary
course of business of the Company or its Subsidiaries, are on normal commercial
terms, and do not involve amounts in

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excess of US$25,000,000 per transaction;

                 (i)  distribute to holders of Common Shares (whether by
dividend or in a merger, amalgamation or consolidation or otherwise) evidences
of indebtedness, any class or series of shares in the capital of the Company,
other securities, cash or assets (other than Common Shares or other securities
referred to in Section 9(a) or a dividend payable exclusively in cash and other
than as a result of a Fundamental Change (as defined in Section 10)); or

                 (j)  amend, repeal, waive or modify any provisions of this
Schedule in any manner.

          For purposes hereof, a Subsidiary shall be deemed to be wholly-owned
by the Company if the Company directly or indirectly beneficially owns all the
outstanding capital stock of such Subsidiary. If the Company or any Subsidiary
of the Company takes any of the foregoing actions without the consent or
affirmative vote of the holders of the Senior Preferred Shares as provided
above, such action shall be deemed to be a variation of the class rights of the
Senior Preferred Shares. The requisite majority approval of the holders of the
Senior Preferred Shares, in accordance with the foregoing, shall be in addition
to any other majority required pursuant to the Bye-laws of the Company.

          7.3.   The STT Group Parent shall be conclusively presumed to have
authority as agent to execute any consent pursuant to Section 7.2 on behalf of
each of its Affiliates.

     8.   Conversion.

          8.1.   Subject to compliance with Bermuda law, each Senior Preferred
Share shall be convertible at any time and from time to time at the option of
the holder thereof into a number of fully paid and nonassessable Common Shares
equal to one multiplied by the Conversion Ratio as of the date of conversion.
The "Conversion Ratio" as of any date shall be a fraction, the numerator of
which shall be 0.01 and the denominator of which shall be the Conversion Price
as of such date. The "Conversion Price" shall be $0.01, subject to adjustment
from time to time as provided in Section 9. The Conversion Ratio as of the first
date of issuance of the Senior Preferred Shares (the "Issuance Date") shall be
1.0.

          8.2.   Conversion of Senior Preferred Shares may be effected by any
holder upon the surrender to the Company at the principal office of the Company
or at the office of any agent or agents of the Company (the "Transfer Agent"),
as may be designated by the Board, of the certificate or certificates for such
Senior Preferred Shares to be converted accompanied by a written notice stating
that such holder elects to convert all or a specified whole number of such
shares in accordance with the provisions of this Section 8 and specifying the
name or names in which such holder wishes the certificate or certificates for
Common Shares to be issued. In case such notice shall specify a name or names
other than that of such holder, such notice shall be accompanied by payment of
all transfer taxes payable upon the issuance of Common Shares in such name or
names. Other than such taxes, the Company shall pay any documentary, stamp or
similar issue or transfer taxes that may be payable in respect of any issuance
or delivery of Common Shares upon conversion of Senior Preferred Shares pursuant
hereto. As promptly as practicable after the surrender of such certificate or
certificates and the receipt of such notice relating thereto and, if applicable,
payment of all required transfer taxes (or the demonstration to the satisfaction
of the

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Company that such taxes have been paid), the Company shall deliver or cause to
be delivered (x) certificates representing the number of validly issued, fully
paid and nonassessable full Common Shares to which the holder (or the holder's
transferee) of Senior Preferred Shares being converted shall be entitled and (y)
if less than the full number of Senior Preferred Shares evidenced by the
surrendered certificate or certificates is being converted, a certificate or
certificates, of like tenor, for the number of shares evidenced by such
surrendered certificate or certificates less the number of shares being
converted. Such conversion shall be deemed to have been made at the close of
business on the date of giving such notice and of such surrender of the
certificate or certificates representing the Senior Preferred Shares to be
converted so that the rights of the holder thereof as to the shares being
converted shall cease except for the right to receive Common Shares and accrued
and unpaid dividends with respect to the Senior Preferred Shares being
converted, in each case in accordance herewith, and the person entitled to
receive the Common Shares shall be treated for all purposes as having become the
record holder of such Common Shares at such time.

          8.3.   If a holder of Senior Preferred Shares exercises conversion
rights under Section 8.1, upon delivery of the shares for conversion, such
shares shall cease to accrue dividends pursuant to Section 4 as of the end of
the day immediately preceding the date of such delivery, but such shares shall
continue to be entitled to receive all dividends declared in respect of such
shares on or before such date. Any such declared dividends shall be payable on
the date paid to other holders of Senior Preferred Shares by the Company as and
when such dividends are paid to any remaining holders or, if none, on the date
which would have been the next succeeding Dividend Payment Date had there been
remaining holders or such later time at which the Company believes it has
adequate available funds under applicable law to make such a payment.

          8.4.   Notwithstanding anything herein to the contrary, but subject to
the provisions of Section 8.3 and to Section 9, upon conversion, no payment or
adjustment shall be made by the Company to any holder of Senior Preferred Shares
surrendered for conversion in respect of any accrued and unpaid dividends on the
Senior Preferred Shares surrendered for conversion.

          8.5.   In connection with the conversion of any Senior Preferred
Shares, no fractions of Common Shares shall be issued, but in lieu thereof, the
Company shall pay a cash adjustment in respect of such fractional interest in an
amount equal to such fractional interest multiplied by the Liquidation
Preference and divided by the Conversion Ratio. If more than one Senior
Preferred Share shall be surrendered for conversion by the same holder at the
same time, the number of full Common Shares issuable on conversion thereof shall
be computed on the basis of the total number of Senior Preferred Shares so
surrendered.

          8.6.   The Company shall at all times reserve and keep available, free
from preemptive rights, for issuance upon the conversion of Senior Preferred
Shares such number of its authorized but unissued Common Shares as will from
time to time be sufficient to permit if necessary the conversion of all
outstanding Senior Preferred Shares. Prior to the delivery of any securities
which the Company shall be obligated to deliver upon conversion of the Senior
Preferred Shares, the Company shall comply with all applicable Bermuda laws
which require action to be taken by the Company. All Common Shares delivered
upon conversion of the Senior Preferred Shares will upon delivery be duly and
validly issued and fully paid, free of all Encumbrances and not subject to any
preemptive rights.

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          8.7.   The manner of conversion of the Senior Preferred Shares shall
be determined by the Board having regard to the provisions of Bermuda law at the
relevant time. The Board shall take all necessary action to ensure that the
holders of the Senior Preferred Shares enjoy the full benefit of the conversion
rights granted hereunder.

          8.8.   The holder of a Senior Preferred Share shall notify the Company
(x) upon the transfer (the "Transfer") of any Senior Preferred Share, or of any
currently exercisable right to vote or cause to be voted, any Senior Preferred
Share (whether by proxy (other than a proxy given in the ordinary course of
business), declaration of trust or otherwise), to any person other than the STT
Group Parent or an Affiliate of the STT Group Parent or (y) if such holder
ceases to be an Affiliate of the STT Group Parent (the "Automatic Conversion
Event"). Upon notice to the Company of an Automatic Conversion Event, each
Senior Preferred Share being Transferred, or held by such holder who ceases to
be an Affiliate of the STT Group Parent, as the case may be, shall automatically
convert into the number of Common Shares into which each Senior Preferred Share
is convertible as at the date of the Automatic Conversion Event in accordance
with the foregoing provisions of this Section 8, and such conversion shall be
deemed to have become effective as of the date of the Automatic Conversion
Event.

     9.   Adjustments.

          (a)    Common Share Splits and Combinations. In case the Company shall
at any time or from time to time after the Issuance Date (i) subdivide or split
the outstanding Common Shares, (ii) combine or reclassify the outstanding Common
Shares into a smaller number of shares, (iii) issue by reclassification of the
Common Shares into any shares in the capital of the Company or (iv) pay a
dividend or make a distribution on Common Shares in Common Shares or other
securities, then, and in each such case, either (x) the Conversion Price in
effect immediately prior to such event or the record date therefor, whichever is
earlier, shall be adjusted, or (y) in the case of a subdivision, split or
combination of the Common Shares, the Senior Preferred Shares shall be similarly
subdivided, split or combined, in each case so that the holder of any Senior
Preferred Shares thereafter surrendered for conversion shall be entitled to
receive the number of Common Shares or other securities of the Company which
such holder would have owned or have been entitled to receive after the
occurrence of any of the events described above, had such Senior Preferred
Shares been surrendered for conversion immediately prior to the occurrence of
such event or the record date therefor, whichever is earlier. An adjustment made
pursuant to this Section 9(a) shall become effective at the close of business on
the day upon which such corporate action becomes effective. Such adjustment
shall be made successively whenever any event listed above shall occur.

          (b)    Senior Preferred Share Splits and Combinations. The Company
shall not subdivide, split, combine or reclassify the Senior Preferred Shares,
other than in a subdivision, split or combination pursuant to Section 9(b) in
connection with an equivalent subdivision, split or combination of the Common
Shares.

          (c)    Below Market Issuance of Equity Securities. In case the Company
shall issue Equity Securities pursuant to an offer to holders of its Common
Shares at a price per share less than the Current Market Price (as defined
below), and such offer is not extended to the holders of the Senior Preferred
Shares, the Conversion Price in effect immediately prior to the close of
business on the record date fixed for determination of holders of Common Shares
entitled to receive such offer shall be reduced by multiplying such

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Conversion Price by a fraction, the numerator of which is the sum of the number
of Common Shares outstanding at the close of business on such record date and
the number of Common Shares that the aggregate offering price of the total
number of Common Shares so issued would purchase at such Current Market Price
and the denominator of which is the sum of the number of Common Shares
outstanding at the close of business on such record date and the number of
additional Common Shares so issued. For purposes of this Section 9(c), the
issuance of rights or warrants to subscribe for or purchase securities
convertible into Common Shares shall be deemed to be the issuance of rights or
warrants to purchase the Common Shares into which such securities are
convertible at an aggregate offering price equal to the sum of the aggregate
offering price of such securities and the minimum aggregate amount (if any)
payable upon conversion of such securities into Common Shares. Such adjustment
shall be made successively whenever any such event shall occur. If the Company
issues any Equity Securities pursuant to an offer to holders of its Common
Shares for consideration other than cash, the amount of non-cash consideration
received by the Company shall be deemed to be the fair market value of the
non-cash consideration, as determined mutually by the Board and the STT Group
Parent (if the STT Shareholder Group beneficially owns the Relevant Percentage),
and if the Board and the STT Group Parent shall fail to agree, at the Company's
expense by an appraiser chosen by the Board and reasonably acceptable to the STT
Group Parent.

     10.  Fundamental Changes. In case any transaction or event (including,
without limitation, any merger, amalgamation, consolidation, sale of assets,
tender or exchange offer, reclassification, compulsory share exchange or
liquidation) shall occur in which all or substantially all outstanding Common
Shares is converted into or exchanged for stock, other securities, cash or
assets (each, a "Fundamental Change"), the holder of each Senior Preferred Share
outstanding immediately prior to the occurrence of such Fundamental Change shall
have the right upon any subsequent conversion to receive (but only out of
legally available funds, to the extent required by applicable law) the kind and
amount of stock, other securities, cash and assets that such holder would have
received if such share had been converted immediately prior thereto.

     11.  Transfer Restrictions.

          11.1.  The Senior Preferred Shares shall bear the following legend:

                 "THE SERIES A SENIOR PREFERRED SHARES, WITH LIQUIDATION
                 PREFERENCE $10.00 PER SHARE, OF THE COMPANY REPRESENTED BY THIS
                 CERTIFICATE MAY NOT BE OFFERED OR SOLD ABSENT REGISTRATION
                 UNDER THE U.S. SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"),
                 AND ANY APPLICABLE STATE SECURITIES LAWS OR AN APPLICABLE
                 EXEMPTION FROM THE REGISTRATION REQUIREMENTS UNDER THE ACT".

          11.2.  The Common Shares issuable upon conversion of the Senior
Preferred Shares shall bear the following legend:

                 "THE COMMON SHARES, PAR VALUE $0.01 PER SHARE, OF THE COMPANY
                 REPRESENTED BY THIS CERTIFICATE MAY NOT BE OFFERED OR SOLD
                 ABSENT REGISTRATION UNDER THE U.S. SECURITIES ACT OF 1933, AS
                 AMENDED (THE

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                 "ACT"), AND ANY APPLICABLE STATE SECURITIES LAWS OR AN
                 APPLICABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS UNDER
                 THE ACT".

     12.  Certain Definitions.

          12.1.  As used in this Schedule, the following terms shall have the
following meanings, unless the context otherwise requires:

          "Current Market Price" of the Common Shares shall mean, as of the date
of determination, (a) the average of the daily Market Price (as determined under
clause (a), (b) or (c) of the definition of Market Price) during the immediately
preceding thirty trading days ending on such date, and (b) if the Common Shares
are not listed or admitted to trading on any national securities exchange or
quoted in the over-the-counter market, then the Market Price as determined under
clause (d) of the definition of Market Price on such date.

          "Encumbrances" shall mean any mortgage, charge (whether fixed or
floating), pledge, lien, hypothecation, assignment, deed of trust, title
retention, security interest or other encumbrance of any kind securing, or
conferring any priority of payment in respect of any person (including without
limitation any right granted by a transaction which, in legal terms, is not the
granting of security but which has an economic or financial effect similar to
the granting of security under applicable law), any proxy, power of attorney,
voting trust agreement, interest, option, right of first offer, negotiation or
refusal, or transfer restriction.

          "Global Marine" means Global Marine Systems Ltd., a company organized
under the laws of England and Wales.

          "Market Price" of the Common Shares as of the date of determination
shall mean (a) if such Common Shares are listed or admitted to trading on a
national securities exchange, the closing price per share of such Common Shares
on such date published in The Wall Street Journal (National Edition) or, if no
such closing price on such date is published in The Wall Street Journal
(National Edition), the average of the closing bid and asked prices on such
date, as officially reported on the principal national securities exchange on
which such Common Shares are then listed or admitted to trading; or (b) if on
the date of determination, such Common Shares are not then listed or admitted to
trading on any national securities exchange but are designated as a national
market system security by the National Association of Securities Dealers, Inc.,
the last trading price of such Common Shares on such date; or (c) if there shall
have been no trading on the date of determination, or if such Common Shares are
not designated as a national market system security by the National Association
of Securities Dealers, Inc., the average of the reported closing bid and asked
prices of such Common Shares on the date of determination, as quoted in the
over-the-counter market; or (d) if such Common Shares are not then listed or
admitted to trading on any national securities exchange, or are not designated
as a national market system security by the National Association of Securities
Dealers, Inc., or are not quoted in the over-the-counter market, then the market
price per share on the date of determination as determined mutually by the Board
and the STT Group Parent (if the STT Shareholder Group beneficially owns the
Relevant Percentage), and if the Board and the STT Group Parent shall fail to
agree, at the Company's expense by an appraiser chosen by the Board and
reasonably acceptable to the STT Group Parent.

          "Related Party" shall mean any person that holds Equity Securities

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<PAGE>

representing at least 10% or more of the Company's outstanding Common Shares,
calculated on a non-diluted and as-converted basis.

          "Relevant Percentage" shall mean Equity Securities representing 15% or
more of the Company's outstanding Common Shares, calculated on a non-diluted and
as-converted basis but excluding the Common Shares, up to a maximum of 3,478,261
(subject to adjustment for share divisions, stock splits, consolidations,
combinations and similar events), reserved or issued under the Share Option
Plan.

          12.2.  In calculations of share numbers, references to a "fully
diluted basis", a "non-diluted basis" and an "as-converted basis" shall have the
meanings set forth in the Bye-laws of the Company.

     13.  Headings. The headings of the Sections of this Schedule are for
convenience of reference only and shall not define, limit or affect any of the
provisions hereof.

     14.  Bye-Laws. This Schedule shall solely for ease of reference be attached
to the Bye-laws of the Company, but shall not form part of the Bye-laws.


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<PAGE>

          IN WITNESS WHEREOF, the Company has caused this Certificate of
Designations to be duly signed on its behalf on this [___] day of [___________].

                                        GLOBAL CROSSING LIMITED
                                        (FORMERLY GC ACQUISITION LTD.), a
                                        company incorporated under the laws of
                                        Bermuda


                                        By:
                                             -----------------------------------
                                             Name:
                                             Title:


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