<PAGE>   1
                                                                    EXHIBIT 4(t)

                              AMENDED AND RESTATED
                            SECURITYHOLDERS AGREEMENT

          THIS AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT (this "Agreement")
is made as of August 18, 2000, among (i) Maxcom Telecomunicaciones, S.A. de C.V.
(formerly known as "Amaritel, S.A. de C.V."), a corporation organized under the
laws of Mexico (the "Company"), (ii) each of the entities listed on the
signature pages hereto as "Investors" (collectively, the "Investors"), (iii) the
shareholders of the Company and the holders of common, non-redeemable
participation certificates (the "CPOs," and the holders of the CPOs, the "CPO
Holders") issued by Banco Nacional de Mexico, S.A., Institucion de Banca
Multiple, Grupo Financiero Banamex Accival, Division Fiduciaria, in its capacity
as the trustee (the "NIT Trustee") of the Neutral Investment Trust (as
hereinafter defined), if any, listed on the signature pages hereto as "Other
Securityholders" (the "Other Securityholders"), (iv) the existing shareholders
of the Company listed on the signature pages hereto as "Existing
Securityholders" (the "Existing Securityholders"), and (v) Jorge Cervantes Trejo
and Alejandro Sainz Orantes jointly and individually as the initial Common
Representative (as defined in the Neutral Investment Trust). The Investors, the
Other Securityholders and the Existing Securityholders are referred to herein
collectively as the "Securityholders" and individually as a "Securityholder."
Except as otherwise indicated herein, capitalized terms used herein are defined
in Section 13 hereof.

          WHEREAS, the Securityholders and the Company entered into a
Shareholders Agreement on May 23, 1998 (the "Original Shareholders Agreement")
for the purposes, among others, of (i) establishing the composition and
operation of the Company's board of directors (the "Board"), (ii) assuring
continuity in the management and ownership of the Company, (iii) limiting the
manner and terms by which the Company Shares may be transferred, and (iv)
providing for certain liquidity rights and remedies upon certain defaults;

          WHEREAS, the execution and delivery of the Original Shareholders
Agreement was a condition to, and in consideration of, certain Investors'
subscription to nominative series N shares of the Company with limited voting
rights and no par value ("Series N Shares"), pursuant to the Subscription
Agreement, dated as of May 8, 1998, among such Investors, the Company and
certain of the Existing Securityholders (as such agreement may be modified or
amended from time to time in accordance with its terms (the "Subscription
Agreement");

          WHEREAS, the execution and delivery of the Irrevocable Administration
and Security Trust Agreement, dated as of May 21, 1998, among the Company, the
Investors, the Existing Securityholders and Bancomer, S.A., Institucion de Banca
Multiple, Grupo Financiero Bancomer, Direccion Fiduciaria, as trustee (the
"Original Security Trust Agreement"), was a condition to the Existing
Securityholders' subscription to nominative, series A shares of the Company with
full voting rights, no par value and which may only be held by Mexican
individuals or Mexican entities with a clause in their by-laws prohibiting
foreign ownership ("Series A Shares") and nominative series B shares of the
Company with full voting rights, no par value and which may be held by Mexican
and foreign individuals or corporations ("Series B Shares") pursuant to the
Subscription Agreement.

          WHEREAS, all of the Series A Shares and Series B Shares beneficially
and actually owned by the Existing Securityholders were previously deposited
into the Irrevocable Administration and Security Trust number F/29206, dated
March 24, 1998, with Bancomer, S.A., Institucion de Banca Multiple, Grupo
Financiero Bancomer, Direccion Fiduciaria, as trustee (the "Nissho Trust") to
secure the Existing Securityholders guarantee of the Company's obligations to
Nissho Iwai American Corporation ("Nissho Iwai") under a certain Credit
Agreement dated as of February 26, 1998 between the Company and Nissho Iwai (as
amended and restated on December 14, 1998, the "Nissho Credit Agreement");

          WHEREAS, on March 17, 2000, the Nissho Credit Agreement was terminated
and on April 25, 2000 the Nissho Trust was terminated;

          WHEREAS, on April 25, 2000, the Series A Shares and Series B Shares
that were previously held in trust by Bancomer, S.A., Institucion de Banca
Multiple, Grupo Financiero Bancomer, Direccion Fiduciaria as




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trustee under the Nissho Trust were deposited with Bancomer, S.A., Institucion
de Banca Multiple, Grupo Financiero Bancomer, Direccion Fiduciaria, as trustee
(the "Security Trust Trustee") under the Original Security Trust Agreement;

          WHEREAS, on August 18, 2000, the Original Security Trust Agreement was
amended and restated by the parties thereto (as amended and restated, and as
amended from time to time thereafter in accordance with its terms and this
Agreement, the "Security Trust Agreement") to, among other things, reflect (i)
the termination of the Nissho Trust, (ii) the release of 255,000 Series A Shares
and 245,000 Series B Shares from the trust estate of the Security Trust, and
(iii) the conversion of such released Series A Shares and Series B Shares into
CPOs (on a two-for-one basis (i.e., the conversion of such released Series A
Shares into one Series C Share and one Series N Share for each two Series A
Shares and the simultaneous deposit of such shares into the Neutral Investment
Trust in exchange for CPOs and the conversion of such released Series B Shares
into one Series C Share and one Series N Share for each two Series B Shares and
the simultaneous deposit of such shares into the Neutral Investment Trust in
exchange for CPOs)) pursuant to the Restructuring (as defined below);

          WHEREAS, on February 21, 2000, the shareholders of the Company
approved, subject to certain conditions precedent, a restructuring of the
Company's capital structure, including the authorization of (i) the issuance of
a new series of shares which are comprised of nominative Series C shares of the
Company with full voting rights and no par value (the "Series C Shares") (which,
under the Company's By-laws, are required to be voted in the same manner as the
majority vote of the Series A Shares), (ii) the creation of an Irrevocable
Neutral Investment Trust (the "Neutral Investment Trust"), into which the
holders of Series N Shares and certain holders of Series A Shares and Series B
Shares would deposit such shares into the trust estate, which shares,
simultaneously with their deposit into the trust estate, will be, in the case of
fifty percent of such Series N Shares, converted into Series C Shares pursuant
to clause (iii) below, and in the case of the Series A Shares and Series B
Shares, will be converted into Series C Shares and Series N Shares pursuant to
clause (iv) below, (iii) the conversion of fifty percent (50%) of the issued and
outstanding Series N Shares into Series C Shares on a one-for-one basis, (iv)
the conversion of 255,000 Series A Shares and 245,000 Series B Shares into
Series C Shares and Series N Shares, with each two Series A Shares or Series B
Shares being converted into one Series C Share and one Series N Share, (v) the
conversion of fifty percent (50%) of the Series N Shares held by the Company as
treasury shares and reserved for issuance pursuant to the terms of various
options granted by the Company into Series C Shares on a one-for-one basis, and
(vi) the issuance by the NIT Trustee of CPOs to the settlors of the Neutral
Investment Trust (with each one CPO representing one Series C Share and one
Series N Share) (collectively, the "Restructuring");

          WHEREAS, the General Bureau of Foreign Investment of the Ministry of
Commerce and Industrial Development (the "Bureau") has reviewed and approved (i)
the Restructuring, (ii) the form of the Company's Irrevocable Neutral Investment
Trust Agreement No. 14515/5 (as executed on August 18, 2000 and as amended from
time to time in accordance with its terms and this Agreement, the "Neutral
Investment Trust Agreement"), and (iii) the issuance of CPOs pursuant to the
Neutral Investment Trust Agreement;

          WHEREAS, the CPO Holders, in accordance with the terms of the Neutral
Investment Trust Agreement and the Issuance Deed dated August 18, 2000 appointed
Jorge Cervantes Trejo and Alejandro Sainz Orantes jointly and individually as
the initial Common Representative;

          WHEREAS, within 30 days after the date hereof, the Company shall hold
a Shareholders meeting for the purpose of approving and adopting the Amended and
Restated By-laws of the Company in the form attached hereto as Exhibit C and the
Company shall file within 10 days thereof with the Bureau for approval all
provisions of the Company's By-laws adopted by the Shareholders which differ
from the form of the Company's By-laws submitted previously to the Bureau for
approval, to the extent that such approval is necessary with respect to such
provisions; and

          WHEREAS, the parties hereto desire to amend and restate the Original
Shareholders Agreement to, among other things, reflect the Restructuring and to
provide that the exchange of Series C Shares and Series N Shares for CPOs and
the deposit of the Series C Shares and Series N Shares into the Neutral
Investment Trust shall not adversely affect in any manner the rights granted to
the holders of the Series N Shares under the Original Shareholders Agreement.




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          NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto hereby amend and restate the
Original Shareholders Agreement to reflect the following agreements:

          1. Board of Directors.

          (a) Each of the Company and the Securityholders agree to take (or
cause to be taken) all necessary actions and agree to exercise, or cause to be
exercised, the voting power of their CPOs and/or Company Shares, as the case may
be, so that:

          (i) at all times the Company shall be managed by the Board and the
     Board shall be composed of no more than thirteen (13) members and thirteen
     (13) alternate members;

          (ii) subject to Section 1(e) below, the following individuals shall be
     elected to the Board:

               (A) four members (and four alternates) designated by the
          Investors in their capacity as CPO Holders (collectively, the "N
          Directors"); provided that:

                    (1) the BAIIC Investors shall be entitled to designate one N
               Director (and one alternate N Director);

                    (2) the Bachow Investors shall be entitled to designate one
               N Director (and one alternate N Director);

                    (3) BancBoston Investments, Inc. ("BancBoston") shall be
               entitled to designate one N Director (and one alternate N
               Director); and

                    (4) Latinvest Strategic Investment Fund, L.P. shall be
               entitled to designate one N Director (and one alternate N
               Director);

               (B) seven members (and seven alternates) designated by the
          holders of a majority of the Series A Shares; and

               (C) two members (and two alternates) designated by the holders of
          a majority of the Series B Shares.

          (iii) at the request of any N Director, each committee of the Board
     (each, collectively with each committee of any Sub Board, a "Committee")
     shall include at least one N Director (designated by the Requisite
     Investors); provided that the Board shall establish a five-member Advisory
     Committee (which shall be responsible for advising the Board regarding, and
     shall oversee, the Company's continuing operations but which shall not have
     the authority to approve any matters and rather which shall only have the
     authority to recommend matters to the full Board) consisting of (A) the
     Company's Chief Executive Officer; (B) Adrian Aguirre; (C) subject to
     Section 1(d) below, the N Directors designated by each of the BAIIC
     Investors and the Bachow Investors; and (D) a Board member designated by CT
     Global Telecommunications, Inc.; provided, further, that notwithstanding
     the foregoing, so long as an Investor holds at least ten percent of the
     CPOs identified next to such Investor's name on the attached Schedule of
     Securityholders which are attributable to the Series N Shares initially
     subscribed for by such Investor pursuant to the Subscription Agreement
     (i.e., excluding, for purposes of determining such percentage, any Series N
     Shares acquired by such Investor subsequent to May 21, 1998), if the N
     Director designated by such Investor is not on the Advisory Committee, the
     Board shall (x) give such Investor written notice of each meeting of that
     Advisory Committee at the same time and in the same manner as notice is
     given to the members thereof, (y) permit a representative of such Investor
     to attend as an observer (or participate via telephone in) all meetings of
     that Advisory Committee and (z) provide





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     to such Investor all written materials and other information (including
     copies of meeting minutes) given to members in connection with such
     meetings at the same time such materials and information are given to the
     such members;

          (iv) at the request of any N Director, the composition of the board of
     directors or similar body of each of the Company's subsidiaries (a "Sub
     Board") shall include at least one N Director (designated by the Requisite
     Investors) and at the request of any N Director, each Committee of a Sub
     Board shall include at least one N Director (designated by the Requisite
     Investors);

          (v) except as otherwise provided in Section 1(e) below, the removal of
     any person (with or without cause) from the Board, a Sub Board or any
     Committee shall be only at the written request of the Securityholder or
     Securityholders who designated such member and under no other
     circumstances;

          (vi) in the event that any person ceases for any reason to serve as a
     member of the Board, a Sub Board or any Committee, the vacancy shall be
     filled by a new member selected by the Securityholder or Securityholders
     who designated such member;

          (vii) in the event that any Board member or Sub Board member cannot
     attend any meeting of the Board, a Sub Board or a Committee of the Board or
     a Committee of a Sub Board, the alternate member designated by the
     Securityholder or Securityholders who designated such member may attend
     such meeting, and such alternate member shall be given all written notices,
     materials and information regarding all meetings of the Board, such Sub
     Board or Committee and shall be entitled to vote at such meeting as a
     member of the Board, such Sub Board or Committee (it being understood that
     any alternate member may nonetheless attend any such meeting of the Board,
     a Sub Board or a Committee of the Board as an observer and shall be
     entitled to receive copies of all materials and information regarding such
     meeting, even if the principal Board member is present); and

          (viii) if any party fails (but is otherwise entitled) to designate a
     Board member pursuant to the terms of this Section 1, such Board member
     seat shall remain vacant until filled in accordance with this Section 1.

          (b) The Company shall indemnify members of the Board, any Sub Board or
any Committee (including alternate members) to the fullest extent permitted
under applicable law for all actions taken by such members (or alternates) in
their capacities as members (or alternates) of the Board, any Sub Board or any
Committee.

          (c) The Company shall pay the reasonable out-of-pocket expenses
incurred by each member of the Board (and alternate) in connection with
attending each meeting of the Board, any Sub Board or any Committee of the Board
attended by such member (and alternate) and other travel expenses reasonably
incurred in discharging such member's duties as a member of the Board, any Sub
Board, Committee of the Board or Committee of a Sub Board.

          (d) After the consummation of a Qualified Public Offering, the rights
of each Investor or group of Investors under this Section 1 to designate an N
Director shall terminate at such time as such Investor or group of Investors
hold(s) in the aggregate less than twenty-five percent (25%) of the number of
CPOs identified next to such Investor's (or group of Investors') name on the
attached Schedule of Securityholders which are attributable to the Series N
Shares initially subscribed for by such Investor (or group of Investors)
pursuant to the Subscription Agreement (i.e., excluding, for purposes of
determining such percentage, any Series N Shares acquired by such Investor (or
group of Investors) subsequent to May 21, 1998). Notwithstanding the foregoing,
prior to or after the consummation of a Qualified Public Offering, each Investor
or group of Investors entitled to designate N Directors pursuant to this Section
1 may assign in writing any right to designate N Directors and/or Committee
members hereunder to any Person or group of affiliated Persons who acquire more
than fifty percent (50%) of the number of CPOs identified next to such
Investor's (or group of Investors') name on the attached Schedule of





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Securityholders which are attributable to the Series N Shares initially
subscribed for by such Investor (or group of Investors) pursuant to the
Subscription Agreement (i.e., excluding, for purposes of determining such
percentage, any Series N Shares acquired by such Investor (or group of
Investors) subsequent to May 21, 1998). In the event that any Investor or group
of Investors assigns any such right to designate an N Director or Committee
member pursuant to the foregoing, such Investor or group of Investors shall
promptly thereafter provide to the Company written notice of such assignment and
the Company shall then promptly provide copies of such written notice to all of
the other Securityholders; provided that, notwithstanding the foregoing, in the
event of any assignment of a right to designate an N Director by either of the
BAIIC Investors or the Bachow Investors pursuant hereto, the replacement for
such N Director to the Advisory Operations Committee shall be designated by the
Requisite Investors

          (e) Notwithstanding anything to the contrary in this Agreement, in
addition to the other remedies provided in Sections 8, 10 and 11 below, upon the
request of the Requisite Investors on or after the delivery of a Call Notice or
an IPO Notice (as contemplated by and provided for in the Security Trust
Agreement) and in a manner consistent with Mexican law and the Mexican grant
(concession) permitting the Company to conduct the Business, all of the members
of the Board and all members of each Sub Board (other than those members
designated by the Investors) shall automatically and promptly be removed and
replaced with persons nominated by the Requisite Investors or their designees,
nominees or assignees, and the Securityholders will take (or cause to be taken)
all actions requested by the Requisite Investors for the purpose of effecting
such removals, electing such nominees and consummating a Specific Qualified
Public Offering, a Sale Transaction (as defined in Section 8(e) below) and/or
the Call (as defined in Section 11 below).

          2. Board and Securityholder Actions.

          2A. The Company and each Securityholder agree to take (or cause to be
taken) all necessary actions so that, in accordance with the Company's By-laws,
the following actions are submitted to the Board for authorization prior to the
taking of any such actions and shall require the approval of (i) at least two
(2) N Directors, so long as the Investors collectively have the right to
designate at least two (2) members of the Board or (ii) one (1) N Director in
the event that the Investors collectively only have the right to designate one
member of the Board (the "Requisite Directors"):

          (a) the incurrence or assumption by the Company and/or any of its
subsidiaries of any indebtedness (including capitalized lease obligations) or
other liabilities (other than trade payables incurred in the ordinary course of
business which are not past due), and the mortgaging, pledging or incurring of a
lien, encumbrance or other restriction on any of the assets or properties of the
Company and/or any of its subsidiaries exceeding U.S. $10,000,000 in the
aggregate at any time then outstanding, or the amendment of any loan agreement,
credit agreement, debenture or related document in connection with any
indebtedness (including capitalized leases) approved pursuant to this Section
2A;

          (b) the issuance of any equity securities (including, without
limitation, (i) the issuance of any Company Shares to the NIT Trustee or (ii)
the issuance or delivery of any Company Shares held or otherwise reserved by the
Company as treasury shares) or debt securities with equity features or other
securities exercisable or convertible into equity securities (including options
and warrants issued on or after the date hereof) or debt securities with equity
features or containing any profit participation features, other than any Company
Shares shown on the attached Schedule of Capitalization of the Company as
reserved for issuance pursuant to the Management Option Plan, the Amended and
Restated Operating Agreement, dated May 21, 1998, between the Company and CT
Global Telecommunications, Inc. (the "Operating Agreement"), the Strategic
Assistance Agreement, dated May 21, 1998, between the Company and Bachow &
Associates (the "Strategic Assistance Agreement," the Engagement Letter dated
November 13, 1997 as amended on March 13, 1998 and April 2, 1998 between the
Company and Amsterdam Pacific LLC (the "Engagement Letter") (which Company
Shares issued thereunder shall not exceed (i) 24,425 Series N Shares in the
aggregate prior to giving effect to the Restructuring and (ii) 12,213 Series C
Shares and 12,213 Series N Shares in the aggregate after giving effect to the
Restructuring) or the Nissho Stock Option Agreement, dated March 24, 1998
between the Company and Nissho Iwai (the "Nissho Stock Option Agreement") (which
Company Shares issued under the Nissho Stock Option Agreement shall not exceed
(i) 337,471 Series N Shares in the aggregate prior to giving effect to the
Restructuring and (ii) 168,736 Series C Shares and 168,736 Series N Shares in
the aggregate after giving effect to the Restructuring), each as in effect on
the date hereof;






                                     E-126
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          (c) (i) the sale, transfer, exchange or other disposal of all or a
significant portion of the assets or capital shares of the Company (including,
but not limited to, any Company Shares held by the Company as treasury shares)
in any form of transaction, (ii) the merger, consolidation, spin-off,
recapitalization, reorganization (including a change in the legal nature of the
Company), dissolution or liquidation of the Company (other than the
Restructuring authorized hereby) or (iii) any of the foregoing with respect to
any subsidiary;

          (d) (i) any assignment by the Company or any of its subsidiaries for
the benefit of creditors or (ii) the voluntary commencement of any proceeding
relating to the Company or any of its subsidiaries under any bankruptcy,
reorganization, insolvency, suspension of payments, dissolution or liquidation
law of any jurisdiction;

          (e) the establishment by the Company of any non-wholly-owned-
subsidiary or the making of any loans or advances to, guarantees for the
benefit of, or investments in, any Person other than a wholly-owned subsidiary
(subject to Section 5(d) below, other than advance payments made to suppliers in
the ordinary course of business up to an aggregate of U.S. $2,000,000
outstanding at any time);

          (f) the redemption, purchase or other acquisition of any of the
Company's equity securities or reduction in capital or any Company Shares,
except as otherwise specifically provided herein;

          (g) the Company's or any of its subsidiaries' entering into any
transaction or series of related transactions with any of the Company's
officers, directors, employees, CPO Holders or shareholders, or any of their
respective Affiliates or any individual related by blood or marriage to any such
Person (collectively, "Restricted Persons") or any Person in which any such
Restricted Person owns a beneficial interest or any Affiliate of any of the
foregoing, other than any such transaction or series of related transactions
involving U.S. $1,000,000 or less in the aggregate over the term of such
transaction(s), and other than any customary banking relationships, in each case
entered into in the ordinary course of business on an arm's length basis and on
terms no less favorable than those available from a third party (in each case as
determined by the Requisite Directors);

          (h) the election, appointment or removal of any of the following key
executives of the Company or any of its subsidiaries: the Chief Executive
Officer, the General Managers of any business units, the Chief Operating
Officer, the Chief Financial Officer, the Director of Marketing and the Chief
Engineer (or any other individual with a similar or more senior title or
position), and the approval of salary, compensation and benefit or other similar
plans for such key executives;

          (i) the approval of the Company's annual business plan and annual
budget for each fiscal year (which shall include, among other things, each of
the items set forth on Exhibit A attached hereto) (as so approved, including any
amendments or modifications thereto permitted by this Section 2A(i), the
"Approved Plan"); the approval of any amendment to, modification of or
expenditures in excess of such Approved Plan; and the approval of the entering
into any material transaction outside of the ordinary course of business and not
contemplated in the Approved Plan, including the entering into of any operating
agreements or strategic assistance agreement in addition to or in replacement of
the Operating Agreement and/or the Strategic Assistance Agreement (except that
no such approval shall be required for variances from the Approved Plan in
respect of capital and other expenditures of not more than U.S. $3,000,000 in
the aggregate over the amount approved; provided that if the annual business
plan and budget are not approved by the Board in accordance with this Section
2A(i), then the Approved Plan shall be the Baseline Plan for such fiscal year,
but only for those cities and territories in which the Company is then operating
pursuant to the most recent approval of the Board;

          (j) entering into any new line of business (other than the Business);

          (k) any agreement which would (under any circumstances) restrict the
Company's or any of its subsidiaries' right or ability to perform the provisions
of this Agreement or any of the other agreements or instruments contemplated
hereby or to conduct its business as currently conducted or as proposed to be
conducted at any time (it being understood that this clause (k) is not intended
to affect in any way the provisions of Section 15 or any other contractual right
or obligation of any Securityholder or the Company);




                                     E-127
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          (l) the manner in which the shares or other interests of any
subsidiary or entity owned by the Company shall be voted at shareholders' or
equivalent meetings of any such subsidiary or entity with respect to any matter
of the type covered by this Section 2;

          (m) any amendments, modifications, waivers or changes to (A) any of
the concessions/licenses granted by the Mexican authorities to conduct the
Business, (B) the Company's By-laws, (C) any of the following, in each case as
in effect on the date hereof: (i) any of the Confidentiality and Non-Compete
Agreements (as defined in the Subscription Agreement), (ii) any of the
Employment Agreements (as defined in the Subscription Agreement), (iii) the
Security Trust Agreement, (iv) the Strategic Assistance Agreement, (v) the
Operating Agreement (including the performance requirements specified therein),
(vi) the Agreement Regarding Participation and Registration Rights, dated May
21, 1998, among the Company, CT Global Telecommunications, Inc., Grupo
Empresarial de Telecomunicaciones, S.A. de C.V., and Trust F/6404 (the
"Participation Agreement"), (vii) the Management Option Plan (as defined in the
Subscription Agreement), (viii) the Guidelines attached hereto as Exhibit F,
(ix) the Engagement Letter, (x) the Nissho Stock Option Agreement, or (xi) the
Side Letter Agreement among the Company, the Subscribers (as defined in the
Subscription Agreement) and the Existing Securityholders, (D) the Neutral
Investment Trust Agreement (as in effect on the date hereof), or (E) any other
agreements to which the Company is a party entered into after the date hereof
with the approval of the Requisite Directors or as of the date hereof, provided
that, notwithstanding anything to the contrary contained herein, members of the
Board designated by any shareholder (or Affiliate thereof) with an interest in,
or party to, any such agreement shall not be entitled to vote on the approval of
any such amendment, modification or change and shall reduce the number of
members required to approve any such matter; and

          (n) any commitment or agreement to do any of the foregoing.

          The approval of the Requisite Directors required for each of the
foregoing actions set forth in this Section 2A in no way limits or otherwise
affects the obligation of the Company to also (i) submit to the Board for
approval other matters which are required by applicable law or the Company's
By-laws to be submitted to the Board for approval or (ii) obtain any other
approvals which may be required by applicable law or the Company's By-laws with
respect to the actions in this Section 2.

          2B. The Company and Securityholders agree to take (or cause to be
taken) all necessary actions so that (i) any matter of the type specified in
Section 2A which is submitted to the shareholders or the Company for approval
and (ii) any amendment, modification or other change to the Company's By-laws
(or the rights, terms or preferences of any equity securities of the Company now
or hereafter issued) shall require the approval of the holders of at least 85%
of the Company Shares then outstanding at the time of such vote (including the
Series C Shares and Series N Shares) (or such higher threshold if set forth in
the Company's By-laws) prior to the taking of any such action.

          3. Exchange of Company Shares for CPOs.

          (a) Each Securityholder understands and acknowledges that the Neutral
Investment Trust Agreement contemplates that (i) certain shareholders of the
Company, including the Investors, will deposit (simultaneously with the
execution of this Agreement) in trust with the NIT Trustee all of the subscribed
and paid Series N Shares owned by such Investors, (ii) simultaneously with the
deposit of such shares, the Company shall convert fifty percent (50%) of such
deposited Series N Shares into subscribed and paid Series C Shares, and (iii)
the NIT Trustee shall subsequently issue CPOs to such shareholders.

          (b) The Company, to the extent permitted by Section 2A(b) and Section
24 of this Agreement, will, from time to time, issue (or take from the Series C
Shares and Series N Shares held by the Company as treasury shares) and deposit
in trust with the NIT Trustee subscribed and paid Series C Shares and subscribed
and paid Series N Shares in connection with the issuance of CPOs upon the
exercise of the stock options listed on the attached Schedule of
Securityholders. With respect to the Company's stock options to acquire Series N
Shares, upon (w) the exercise of such a Company stock option, (x) the Company's
receipt of the requisite consideration thereunder, (y) the optionee's compliance
with the terms of this Agreement, including the execution of such optionee of a
counterpart signature page to this Agreement which binds it to the provisions of
this Agreement, and (z) the optionee's compliance with the terms of Neutral
Investment Trust Agreement relating to the admission of





                                     E-128
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new settlors thereunder, the Company will cause the NIT Trustee to issue CPOs to
such option holders in lieu of Series N Shares previously issuable pursuant to
such stock option (with the number of CPOs being issued thereunder equal to one
CPO for each two Series N Shares previously issuable pursuant to such stock
option). Each Securityholder understands and acknowledges that (i) such actions
do not violate the terms of the Original Shareholders Agreement, and (ii) only
to the extent such actions are expressly permitted by Section 2A(b) or Section
24 of this Agreement, such actions will not violate the terms of this Agreement.

          4. Representations and Warranties.

          (a) Each Securityholder individually (and not jointly or severally)
represents and warrants that (i) after giving effect to the Restructuring, such
Securityholder is the beneficial and/or record owner of the number and type of
Company Securities set forth opposite its name on the Schedule of
Securityholders attached hereto, (ii) this Agreement has been duly authorized,
executed and delivered by such Securityholder and constitutes the valid and
binding obligation of such Securityholder, enforceable in accordance with its
terms and (c) such Securityholder has not granted and will not grant and is not
and will not be a party to any proxy, voting trust or other agreement which is
inconsistent with, conflicts with or violates any provision of this Agreement.

          (b) The Company represents and warrants that attached hereto as (i)
the Schedule of Securityholders is an accurate and complete list of each
beneficial and/or record owner (and option holder) of Company Securities (after
giving effect to the Restructuring), including next to each Securityholder's
name, the number and type of Company Securities beneficially and/or of record
owned by such Securityholder (or option holder) and an accurate and complete
list of any other Company Securities reserved for future issuance (upon the
exercise of options, warrants or otherwise), (ii) the Schedule of Capitalization
of the Company is an accurate and complete list of each beneficial and/or record
owner (and option holder) of Company Shares (immediately prior to the
Restructuring), including next to each shareholder's (or option holder's) name,
the number and type of Company Shares beneficially and/or of record owned by
such shareholder (or option holder) and an accurate and complete list of any
other Company Shares reserved for future issuance (upon the exercise of options,
warrants or otherwise), and (iii) the Schedule of Capitalization of the Company
is an accurate and complete list of each beneficial and/or record owner (and
option holder) of Company Shares (after giving effect to the Restructuring)
(including the NIT Trustee), including next to each shareholder's (or option
holder's) name, the number and type of Company Shares beneficially and/or of
record owned by such shareholder (or option holder) and an accurate and complete
list of any other Company Shares reserved for future issuance (upon the exercise
of options, warrants or otherwise). The Company further represents that the
ownership of all of the Series A Shares previously owned of record by Trust No.
F/6404 have been transferred to Trust F/29549.

          (c) The Company further represents and warrants that (i) this
Agreement has been duly authorized, executed and delivered by the Company and
constitutes the valid and binding obligation of the Company, enforceable in
accordance with its terms and (ii) the Company is not a party to any agreement
which is inconsistent with, conflicts with or violates any provision of this
Agreement.

          (d) The Company further represents and warrants that the Guidelines
attached as Exhibit E were duly adopted by the Company on May 21, 1998.

          5. Covenants.

          (a) Financial Statements and Other Information. The Company shall
deliver to each Securityholder and each Member of the Board:

          (i) at least 30 days, but not more than 90 days, prior to the
     beginning of each fiscal year, a strategic business plan and budget,
     prepared on a monthly basis for the Company and its subsidiaries for such
     fiscal year (displaying anticipated statements of income, cash flows and
     balance sheets and including investment requirements, assessments of the
     market, 3-year financial projections and the other items set forth in
     Exhibit A hereto);




                                     E-129
<PAGE>   9

          (ii) (A) promptly upon preparation thereof any other significant
     budgets prepared by the Company and any revisions of such Approved Plan or
     other budgets; (B) within 20 days after any monthly period, a report
     comparing actual performance against that month's budgetary projections
     contained in the Approved Plan and containing at least the information
     specified in Exhibit B hereto and other information and data reasonably
     requested by the Investors; and (C) within 20 days after any monthly period
     in which there is a material adverse deviation from the Approved Plan, an
     officer's certificate explaining the deviation and what actions the Company
     has taken and proposes to take with respect thereto;

          (iii) as soon as available but not more than 30 days after the end of
     each quarterly accounting period in each fiscal year, unaudited
     consolidating and consolidated statements of income and cash flows of the
     Company and its subsidiaries for such quarterly period and for the period
     from the beginning of the fiscal year to the end of such quarter, and
     unaudited consolidating and consolidated balance sheets of the Company and
     its subsidiaries as of the end of such quarterly period, setting forth in
     each case comparisons to the Approved Plan and to the corresponding period
     in the preceding fiscal year, and all such statements shall be prepared in
     accordance with Mexican generally accepted accounting principles and shall
     be certified by an officer of the Company;

          (iv) (a) accompanying the financial statements referred to in Section
     5(a)(iii), an officer's certificate stating that (1) there is no Event of
     Noncompliance in existence and that neither the Company nor any of its
     subsidiaries is in default under any of its other material agreements, the
     concession/license granted by the Mexican government to conduct the
     Business or the Guidelines and (2) the Company and its Subsidiaries have
     fully complied with the laws referenced in Section 5(b)(v), including the
     United States Foreign Corrupt Practices Act (the "FCPA"), and/or (b)
     promptly (but, in any event, within five business days) after the discovery
     or receipt of notice of any Event of Noncompliance, any noncompliance with
     the FCPA, any default under any material agreement to which it or any of
     its subsidiaries is a party which is not cured within five days, any
     condition or event which is reasonably likely to result in any material
     liability under any federal, state or local statute or regulation relating
     to public health and safety, worker health and safety or pollution or
     protection of the environment or any other material adverse change, event
     or circumstance affecting the Company or any subsidiary (including, without
     limitation, the filing of any material litigation against the Company or
     any subsidiary or the existence of any dispute with any Person which
     involves a reasonable likelihood of such litigation being commenced), an
     officer's certificate specifying the nature and period of existence thereof
     and what actions the Company and its subsidiaries have taken and propose to
     take with respect thereto;

          (v) within 90 days after the end of each fiscal year (with respect to
     financial statements prepared in accordance with Mexican generally accepted
     accounting principles) and 120 days after the end of each fiscal year (with
     respect to United States generally accepted accounting principles),
     consolidating and consolidated statements of income and cash flows of the
     Company and its subsidiaries for such fiscal year, and consolidating and
     consolidated balance sheets of the Company and its subsidiaries as of the
     end of such fiscal year, setting forth in each case comparisons to the
     Approved Plan and to the preceding fiscal year, all prepared in accordance
     with both Mexican and United States generally accepted accounting
     principles (together with a reconciliation thereof) and accompanied by (a)
     with respect to the consolidated portions of such statements, an opinion of
     BDO International S.C. or another independent accounting firm acceptable to
     the Requisite Investors (which contains no qualifications that relate to
     limitations on the scope of the audit or an adverse condition with respect
     to the Company or an adverse act by the Company, excluding currency
     devaluations, force majeure events and acts of god), (b) a certificate from
     such accounting firm, addressed to the Board, stating that in the course of
     its examination nothing came to its attention that caused it to believe
     that there was an Event of Noncompliance in existence or that there was any
     other default by the Company or any subsidiary in the fulfillment of or
     compliance with any of the terms, covenants, provisions or conditions of
     any other material agreement to which the Company or any subsidiary is a
     party or, if such





                                     E-130
<PAGE>   10

     accountants have reason to believe any Event of Noncompliance or other
     default by the Company or any subsidiary exists, a certificate specifying
     the nature and period of existence thereof, and (c) a copy of such firm's
     annual management letter to the Board;

          (vi) promptly upon receipt thereof, any additional reports, management
     letters or other detailed information concerning significant aspects of the
     Company's operations or financial affairs given to the Company by its
     independent accountants (and not otherwise contained in other materials
     provided hereunder);

          (vii) within ten days after transmission thereof, copies (in English)
     of all financial statements, proxy statements, reports and any other
     general written communications which the Company sends to its shareholders
     and copies of all registration statements and all regular, special or
     periodic reports (other than those related solely to routine technical
     matters) which it files, or any of its officers or directors file, with
     respect to the Company, with the Bureau, the National Banking and
     Securities Commission and the Ministry of Communications and Transportation
     or the U.S. Securities and Exchange Commission or with any securities
     exchange on which any of its securities are then listed, and copies of all
     press releases and other statements made available generally by the Company
     to the public concerning material developments in the Company's and its
     subsidiaries' businesses; and

          (viii) with reasonable promptness, such other information and
     financial data concerning the Company and its subsidiaries as any Person
     entitled to receive information under this Section 5(a) may reasonably
     request in connection with the monitoring of their investment in the
     Company or their activities as a member of the Board.

Each of the financial statements referred to in Sections 5(a)(iii) and 5(a)(v)
shall be true and correct in all material respects as of the dates and for the
periods stated therein, subject in the case of the unaudited financial
statements to changes resulting from normal year-end adjustments for recurring
accruals (none of which would, alone or in the aggregate, be materially adverse
to the condition (financial or otherwise), operating results, assets, operations
or business prospects of the Company and its subsidiaries taken as a whole).

          All financial statements and other deliveries required under this
Section 5(a) shall be expressed in both U.S. dollars and Mexican pesos (or the
then current Mexican currency).

          (b) Certain Affirmative Covenants. The Company shall, and shall cause
each of its subsidiaries to: (i) at all times cause to be done all things
necessary to maintain, preserve and renew its corporate existence and all
material licenses, concessions, authorizations and permits necessary to the
conduct of its businesses; (ii) maintain and keep its properties in good repair,
working order and condition, and from time to time make all necessary repairs,
renewals and replacements, so that its businesses may be properly conducted at
all times; (iii) continue to operate its business, carry on its activities and
enter into transactions only in the ordinary course of business as is customary
for the Company and each such subsidiary and consistent with the Company's and
each such subsidiary's past practices; (iv) if a dividend is declared or paid on
any one series or class of shares of the Company, declare or pay (on a pro rata
basis) the same dividend on each other series and class of shares of the Company
(other than with respect to dividends declared or paid in shares of the Company
which shall be declared or paid in the series or class of shares on which they
are made) and (v) comply with (and from time to time, including without
limitation, upon request, provide evidence to the Investors of the compliance
with) the Guidelines and all applicable laws, rules, regulations and policies
(as they may be amended from time to time) of: (A) the United States of America,
including, without limitation, the FCPA, the export controls imposed by the U.S.
Department of Commerce, the International Traffic in Arms Regulations, the
restrictions imposed by the U.S. Office of Foreign Assets Control and the
anti-boycott regulations administered by the U.S. Department of Commerce and the
U.S. Department of the Treasury, in each case to the extent compliance with such
laws does not violate any applicable Mexican or other laws, and (B) Mexico,
including all Mexican telecommunications, foreign investment, corporate and tax
laws, rules, regulations and policies and all Mexican reporting requirements;
provided that the Company shall effect such compliance with United States and
Mexican laws in a manner consistent with the terms of this Agreement.





                                     E-131
<PAGE>   11

          (c) Qualified Public Offering. Without prejudice to the provisions of
Section 2A above requiring the consent of the Requisite Directors for certain
actions, (i) prior to May 21, 2002 (the fourth anniversary of the date of the
Original Shareholders Agreement), the Company and the Existing Securityholders
shall use their reasonable best efforts to cause the Company to consummate a
Qualified Public Offering as promptly as practicable after the date of this
Agreement and, (ii) on and after May 21, 2002, the Company and the Existing
Securityholders shall use their best efforts to cause the Company to consummate
a Qualified Public Offering as promptly as practicable after such date (provided
that in neither case shall the Existing Securityholders be obligated to incur
any material out-of-pocket expenses in connection therewith).

          (d) No U.S. Activities. The Company and the Securityholders understand
and acknowledge that the Regulated Investors are regulated under Regulation K
promulgated under the U.S. Bank Holding Company Act, as amended. In this
respect, the Company shall not, and shall not permit its subsidiaries to,
directly or indirectly engage in or transact any business or activities in, or
carry on or maintain a place of business, or invest in or own any entity engaged
in or transacting any business in, the United States without the prior written
consent of each Regulated Investor (provided that this shall not prohibit the
Company from providing long distance telephone service from Mexico to the United
States). In the event that the Company desires to engage in any activity which
would violate this Section 5(d), the Regulated Investors agree to cooperate and
work with the Company to develop (if reasonably feasible) an alternate
arrangement or structure which would be permissible under Regulation K
promulgated under the U.S. Bank Holding Company Act, as amended.

          (e) Inspection of Property. The Company shall permit any
representative designated by a member of the Board at such times as any such
Person may reasonably request during regular business hours after prior written
notice of at least two business days, to (i) visit and inspect any of the
properties of the Company and its subsidiaries, (ii) examine and copy the
corporate and financial records of the Company and its subsidiaries and (iii)
discuss the affairs, finances and accounts of the Company and its subsidiaries
with the directors, officers, key employees and independent accountants of the
Company and its subsidiaries.

          (f) Preemptive Rights. Except for issuances of (i) Company Shares
pursuant to an underwritten public offering registered under the securities laws
of Mexico and/or the United States of America, (ii) options to acquire Company
Shares pursuant to the Management Option Plan (as defined in the Subscription
Agreement), the Operating Agreement and the Strategic Assistance Agreement
(each, as in effect on the date hereof), the Engagement Letter (which shall not
exceed (i) 24,425 Series N Shares in the aggregate prior to giving effect to the
Restructuring and (ii) 12,213 Series C Shares and 12,213 Series N Shares in the
aggregate after giving effect to the Restructuring)), the Nissho Stock Option
Agreement) (which Company Shares issued under the Nissho Stock Option Agreement
shall not exceed (i) 337,471 Series N Shares in the aggregate prior to giving
effect to the Restructuring and (ii) 168,736 Series C Shares and 168,736 Series
N Shares in the aggregate after giving effect to the Restructuring), or other
share option plans approved by the Board in accordance with Section 2 (and
issuances of Company Shares upon the exercise of such options), (iii) shares of
the Company to Regulated Investors pursuant to Section 7 below, and (iv) Company
Shares upon the exercise of the options or warrants outstanding on the date
hereof and described on the Schedule of Capitalization of the Company attached
hereto on the terms specified in the Subscription Agreement, if the Company
proposes to issue any (x) Company Shares or (y) any of its other equity
securities, debt securities containing equity features or other securities
convertible into or containing options or rights to acquire any such debt or
equity securities ("Other Securities" and, together with the securities referred
to in clause (x), "Securities"), the Company shall deliver written notice to all
of the Securityholders, including the Common Representative (the "Preemptive
Rights Notice"), and shall (in addition to all other rights and obligations
under applicable law, and in addition to any required approvals under Section 2A
above) first offer to sell to each holder of the series or class of Company
Shares being issued (only in the case of the issuance of Company Shares) (and
including the NIT Trustee in the case of any issuance or sale of Series C Shares
or Series N Shares) or each shareholder (including the NIT Trustee) of the
Company (only in the case of the issuance of Other Securities), a portion of
such Securities equal to the quotient determined by dividing (1) the sum of the
number of Company Shares of the series or class being issued (only in the case
of the issuance of Company Shares) ("Specific Shares") or Company Shares (only
in the case of the issuance of Other Securities) held by such shareholder
(including with respect to the NIT Trustee, all of the Series C Shares and
Series N Shares in the Neutral Investment Trust), by (2) the sum of the total
number of Specific Shares or Company Shares, as applicable, outstanding on a
fully diluted basis. Each such shareholder (each, an "Eligible Shareholder")
shall (subject to the remainder of this Section 5(f)) be entitled to purchase
such Securities at the most favorable price and on the most favorable terms as
such Securities





                                     E-132
<PAGE>   12

are to be offered to any other Persons by delivering written notice to the
Company within 30 days after the delivery of the Preemptive Rights Notice;
provided that, at the request of the NIT Trustee or any Regulated Investor that
is an Eligible Shareholder, the Company shall offer to the NIT Trustee and/or
such Regulated Investor Securities with terms (satisfactory to the NIT Trustee
and/or such Regulated Investor) that are identical to such Securities being
offered except that such Securities shall have no voting rights and shall be
convertible: (i) in the case of Series N Shares, into limited voting Securities
(to the extent permitted by applicable law), and (ii) in the case of Series C
Shares, into Securities (to the extent permitted by applicable law) of which the
voting rights shall be restricted in such a manner that such Securities must be
voted in the same manner as the majority vote of the Series A Shares; and
provided further that if the Company issues or sells any shares of any series or
class of its equity securities, it shall issue and sell (on a pro rata basis and
at the same price and on the same terms described above) shares of each other
series and class of its equity securities.

          Any Securities elected to be subscribed to by Eligible Shareholders in
accordance with the foregoing shall be sold to such Eligible Shareholders on the
terms specified in the Preemptive Rights Notice. If any Eligible Shareholders do
not elect to subscribe to the Securities, the Company may issue and sell such
Securities to the electing Eligible Shareholders and other Persons on the terms
set forth in the Preemptive Rights Notice for a period of 90 days after the
expiration of the 30 day period after the delivery of the Preemptive Rights
Notice. Any Securities not sold within such 90 day period shall be reoffered to
Eligible Shareholders in accordance with the provisions of this Section 5(f)
(including the time periods contained herein). Notwithstanding the foregoing, in
the event that an electing Eligible Shareholder is not permitted under Mexican
law to hold the amount or type of Securities to which such electing Eligible
Shareholder would be entitled upon exercise of its rights under this Section
5(f), then the electing shareholder shall have the right to designate another
purchaser who would be qualified under Mexican law to purchase such securities
or, at the election of the electing shareholder, the Company shall instead give
to such electing Eligible Shareholder the right (to the extent permitted under
Mexican law) to subscribe to (i) Series N Shares or other Securities which have
identical rights as the Securities being offered except that voting rights shall
be limited to the minimum extent necessary to effect such compliance, and (ii)
Series C Shares that must be voted in the same manner as the majority vote of
the Series A Shares.

          (g) Confidentiality. Each Securityholder agrees that it shall use its
reasonable efforts to, and shall use its reasonable efforts to cause its
respective directors, officers, employees, former employees, advisors and
Affiliates to, keep any information or materials which (i) pertain to the
Company or its subsidiaries or their respective businesses or (ii) pertain to
matters designated as proprietary and confidential by the Company (collectively,
"Confidential Information") confidential; provided that (A) any Confidential
Information required by law, regulators or legal or administrative process to be
disclosed may be disclosed without violating the provisions of this Section
5(g), (B) the Securityholders may disclose Confidential Information to their
respective directors, officers, employees, former employees, advisors,
investors, partners and Affiliates ("Affiliated Parties") and their respective
Affiliated Parties if the disclosing party believes that such disclosure is
necessary or desirable in connection with the transactions contemplated hereby,
(C) the Securityholders (or any of their Affiliated Parties and their respective
Affiliated Parties) may disclose Confidential Information in connection with the
sale or transfer of any portion of Company Securities so long as such Person's
transferee agrees in writing to be bound by the provisions hereof (provided that
such sale or transfer does not violate any provisions of this Agreement, and (in
the case of CPOs), the Neutral Investment Trust Agreement) and (D) this Section
5(g) shall not prohibit the Securityholders from disclosing any Confidential
Information that is available to the public on the Closing Date, or which
thereafter becomes available to the public other than as a result of a breach of
this Section 5(g).

          (h) UBTI. Notwithstanding any provision of this Agreement to the
contrary the Company shall not undertake any activity, operate any trade or
business, or take any action, including without limitation the borrowing of
money or the incurring of any other indebtedness, obligation, or liability, that
would cause any Securityholder, any partner of any Securityholder, or any Person
owning, directly or indirectly, any interest in a Securityholder or the Company,
whose income is exempt from United States federal income tax (each, an "Affected
Person"), to have or incur any unrelated business taxable income (as defined in
Sections 511 through 514 of the United States Internal Revenue Code) on account
of such activity or action without the express prior written consent of each
Securityholder who is (or is acting on behalf of) an Affected Person, which
consent may be granted, withheld or conditioned in such Securityholder's
respective sole and absolute discretion.





                                     E-133
<PAGE>   13

          (i) By-Laws. The Company covenants and agrees to take all actions
necessary to cause the the By-laws of the Company substantially in the form
attached hereto as Exhibit C (with any such changes thereto subject to the
written approval of all of the Investors and the Company) to be approved and
adopted by the Shareholders of the Company, including without limitation, within
30 days of the date hereof to cause a Shareholders' Meeting for the purpose of
approving and adopting the By-laws of the Company in the form attached hereto as
Exhibit C (with any such changes thereto subject to the written approval of a
majority of the Investors and the Company) to be held and the Company shall file
within 10 days thereof such By-laws with the Public Registry of Property and
Commerce of Mexico, Federal District. Each Securityholder hereby approves the
form of the Company's By-laws attached hereto as Exhibit C (the "Company's
By-Laws") and covenants to vote (or cause to be voted) the Shares beneficially
owned by such Securityholder in favor of the adoption of such form of such
By-laws (including any such changes thereto that are approved by a majority of
the Investors and the Company) at the Special Shareholders' Meeting contemplated
by this Section 5(i).

          (j) Bureau of Foreign Investment. Within ten (10) days after the
approval of any amendments to or restatements of the Company's By-laws by the
shareholders of the Company (including the amendment contemplated by Section
5(i) hereof), the Company shall file with the Bureau for approval all provisions
of such By-laws, as amended, which differ from the form of the Company's By-laws
submitted previously to the Bureau for approval, to the extent that such
approval is necessary with respect to any such provisions.

          (k) Termination of Neutral Investment Trust. Neither the Company
(including any of the Company's officers, directors, employees and agents) nor
any CPO Holder shall consent to a termination of the Neutral Investment Trust if
such termination would result in a liquidation of the Neutral Investment Trust
unless this Agreement is amended pursuant to the terms hereof to address the
anticipated post-termination capital structure of the Company and
post-termination relationship of the Securityholders and (i) the CPO Holders
receive a certificate of participation in a successor neutral investment trust
or other instrument, in form and substance reasonably satisfactory to a majority
of the CPO Holders, on a one-for-one basis for the liquidated CPOs, or (ii) the
Company's By-laws are amended to either (1) permit the ownership of the Series C
Shares and Series N Shares directly by the CPO Holders or (2) create one or more
series of stock of the Company (A) which may be held directly by the CPO Holders
and (B) into which the Series C Shares and Series N Shares held by the NIT
Trustee shall be converted prior to the liquidation of the Neutral Investment
Trust. In connection with a proposed termination of the Neutral Investment
Trust, at the written request of a majority of the CPO Holders, the Company and
the Existing Securityholders agree to use their best efforts to cause such an
amendment to the Company's by-laws to be adopted and approved.

          6. Restrictions on Transfer of Company Securities.

          (a) Transfer of Securities. No Securityholder shall directly or
indirectly Transfer any interest in its Company Securities except pursuant to
the provisions of this Section 6 (other than a Transfer pursuant to Sections 7,
8, 9, 10 or 11 (an "Exempt Transfer")), and also, in the case of CPOs, the
Neutral Investment Trust Agreement. With respect to the CPOs, to the extent that
any restriction on transfer contained in the Neutral Investment Trust Agreement
is inconsistent with the restrictions on transfer contained herein, the
Securityholders agree that both transfer restriction provisions shall apply.

          (b) Retention. Notwithstanding anything to the contrary contained in
this Agreement, except with respect to Exempt Transfers and Transfers permitted
by Section 6(f) below, no holder of Series A Shares or Series B Shares shall
Transfer any Company Shares until the first to occur of (i) January 1, 2001 and
(ii) a Qualified Public Offering.

          (c) First Refusal Rights. Subject to Section 6(b), at least 30 days
prior to the Transfer of an interest in any Company Securities (other than
pursuant to an Exempt Transfer), each Securityholder who is not an Investor (the
"Transferring Securityholder") shall deliver to the Secretary of the Board (and,
in the case of a proposed Transfer of CPOs, to the Common Representative and
each CPO Holder), and the Secretary of the Board or the Common Representative,
as the case may be, shall then promptly (but in any event within 5 days) deliver
to the other Securityholders a notice (the "Offer Notice") disclosing the number
of Company Securities to be transferred, the proposed price, terms and
conditions of the Transfer and the identity of the prospective transferee(s) who
submitted the offer. The other Securityholders (on a pro rata basis) may elect
to purchase all (but not less than





                                     E-134
<PAGE>   14

all) of the Company Securities to be transferred on the same terms and
conditions as those set forth in the Offer Notice by giving written notice to
the Transferring Securityholder within 30 days after the Offer Notice has been
given to the Secretary of the Board or Common Representative, as the case may
be. If the other Securityholders elect to purchase all such Company Securities
hereunder, the Transfer of such Company Securities shall be consummated as soon
as possible after the delivery of the election notice(s) to the Transferring
Securityholder, but in any event within 15 days after the expiration of such
30-day period. If the other Securityholders do not elect to purchase all of the
Company Securities specified in the Offer Notice, the remaining Company
Securities shall be reoffered on a pro rata basis to those Securityholders
electing to purchase offered Company Securities by delivery of an additional
written notice. If within 10 days of the delivery of such additional notice the
other electing Securityholders have not elected to purchase all of the Company
Securities specified in the Offer Notice, the Transferring Securityholder may
transfer the Company Securities specified in the Offer Notice to the
transferee(s) specified in the Offer Notice at a price and on terms no more
favorable to the transferee(s) than specified in the Offer Notice for a period
of no more than 60 days after the 45 days after delivery of the Offer Notice.
Any Company Securities not transferred within such 60-day period shall remain
subject to the provisions of this Section 6(c).

          Notwithstanding the foregoing, in the event that an electing
Securityholder is not permitted under Mexican law to hold the amount or type of
Company Securities to which such electing Securityholders would be entitled upon
the exercise of its rights under this Section 6(c), then the electing
Securityholder shall have the right to designate another purchaser who would be
qualified under Mexican law to purchase such Company Securities or, at the
election of the electing Securityholder, the Company shall agree (to the extent
permitted under Mexican law) to exchange such Company Securities to be purchased
by the electing Securityholder (pursuant to the exercise of its rights under
this paragraph Section 6(c)) for other securities of the Company which have
identical rights as such Company Securities being transferred except that, in
order to comply with applicable law, the voting rights of such securities shall
be limited to the minimum level necessary to effect such compliance. In the
event of a substitution for such securities of Series C Shares and Series N
Shares, the electing Securityholder agrees to deposit (or cause to be deposited)
all of such Series C Shares and Series N Shares into the Neutral Investment
Trust in exchange for CPOs.

          (d) Participation Rights. After the required delivery by a
Transferring Securityholder of an Offer Notice to the Secretary of the Board (or
to the Common Representative and each CPO Holder, as the case may be), the other
Securityholders may elect to participate in the contemplated Transfer (other
than an Exempt Transfer but including a Transfer pursuant to Section 6(c)) by an
Existing Securityholder or an Other Securityholder at the same price per share
and on the same terms by giving written notice to the Transferring
Securityholder within 20 days after delivery of the Offer Notice to the Company.
Each participating other Securityholder may sell in the contemplated Transfer,
at the same price and on the same terms specified in the Offer Notice, a number
of Company Securities (whether Series A, Series B, Series C or Series N Shares
or CPOs) equal to the product of (i) the quotient determined by dividing the
percentage of Company Securities (including any CPOs) owned by such Person by
the aggregate percentage of Company Securities (including any CPOs) owned by the
Transferring Securityholder and the other participating Securityholders and (ii)
the Company Securities (including any CPOs) to be sold in the contemplated
Transfer. For the purposes of such calculation, each CPO owned by a
Securityholder shall count as two Company Shares (as adjusted for any stock
splits or reverse-stock splits of the Series C Shares or Series N Shares).

     For example, if the Offer Notice contemplated a sale of 100 Company Shares
     by the Transferring Securityholder, and if the Transferring Securityholder
     at such time owns 30% of all of the Company Shares outstanding and the sole
     other participating Securityholder elects to participate and owns 20% of
     all of the Company Shares outstanding, the Transferring Securityholder
     would be entitled to sell a total 60 shares (30%, 50% x 100 shares) and
     such other Securityholder would be entitled to sell a total of 40 shares
     (20%, 50% x 100 shares).

          No Transferring Securityholder shall transfer any of its Company
Securities to any prospective transferee if such prospective transferee(s)
decline to allow the participation on the terms provided in this Section 6(d) of
the other Securityholders who have elected to so participate.




                                     E-135
<PAGE>   15

          (e) Right of First Offer on Transfers of CPOs by Investors. Subject to
Section 6(b), in the event that any Investor desires to Transfer any CPOs (other
than pursuant to an Exempt Transfer), such Investor shall first offer to sell
such CPOs by delivering to the Common Representative (who shall deliver a copy
of such notice to the Secretary of MAXCOM and such Secretary shall then promptly
(but in any event within 5 days) deliver a copy thereof to the Company's
shareholders) and each of the other CPO Holders written notice thereof (the
"Investor Transfer Notice") disclosing the number of CPOs sought to be
Transferred, the proposed price of the Transfer and the other material economic
terms of the proposed Transfer. The other Securityholders (including the
Investors) holding greater than five percent (5%) of the Company Shares (whether
Series A, Series B, Series C or Series N Shares, and assuming for such
calculation that the ownership of a CPO shall count as the ownership of two
Company Shares (as adjusted for any stock splits or reverse-stock splits of the
Series C Shares or Series N Shares)) on a fully-diluted basis may elect to
purchase all (but not less than all) of the CPOs to be Transferred on a pro rata
basis and at the same price specified in the Investor Transfer Notice by giving
written notice to such transferring Investor within 30 days after the Investor
Transfer Notice has been given to the Common Representative. If such other
Securityholders elect to purchase all such CPOs hereunder, the Transfer of such
CPOs shall be consummated as soon as possible after the delivery of the election
notice(s) to the transferring Investor, but in no event within 15 days after the
expiration of such 30-day period. If such other Securityholders do not elect to
purchase all of the CPOs specified in the Investor Transfer Notice, the
remaining CPOs shall be reoffered on a pro rata basis to those Securityholders
electing to purchase offered CPOs by delivering an additional written notice via
facsimile, with a copy of such notice sent by overnight mail. If within 10 days
of the delivery of such additional notice the other electing Securityholders
have not elected to purchase all of the CPOs specified in the CPO Transfer
Notice, the transferring Investor may, for a period of 180 days after the
expiration of such period, Transfer the CPOs specified in the Investor Transfer
Notice to one or more parties at a price and on other material economic terms no
more favorable to the transferees thereof than the price per share and other
material economic terms offered to such other Investors in the CPO Transfer
Notice. Notwithstanding the foregoing, a transferring Investor shall have the
right to deliver one or more subsequent Investor Transfer Notices if no Transfer
has occurred in accordance with the terms hereof after the expiration of any
such 180-day period. For purposes of this Section 6(e) only, the term "Investor"
shall include CTGT with respect to its CPOs only.

          (f) Permitted Transfers. The restrictions set forth in this Section 6
shall not apply to any Transfer of Company Securities by any Securityholder (i)
in the case of an individual Securityholder, pursuant to applicable laws of
descent or (other than in the case of Adri<n Aguirre) among such
Securityholder's Family Group or (ii) among the Securityholders and/or their
Qualified Affiliates (provided that such Qualified Affiliate(s) shall reconvey
any such Company Securities to the transferring Securityholder(s) at such time
as the Qualified Affiliate ceases to be a Qualified Affiliate) or among or
between the Bachow Investors and/or the BAIIC Investors (the Persons specified
in clauses (i) and (ii) above are collectively referred to herein as "Permitted
Transferees"); provided that the restrictions contained in this Section 6 shall
continue to be applicable to the Company Securities after any such Transfer to a
Permitted Transferee, and provided further that the Permitted Transferees of
such Company Securities shall have agreed in writing to be bound by the
provisions of this Agreement affecting the Company Securities so transferred,
and in the case of a permitted transfer of CPOs, also by the provisions of the
Neutral Investment Trust Agreement.

          (g) Agreement Upon Transfer or Issuance. Prior to Transferring any
Company Securities to any Person, each transferring Securityholder shall cause
the prospective transferee to be (i) bound by this Agreement as if such Person
were the same as such transferring Securityholder, (ii) in the case of a
transfer of CPOs, bound by the Neutral Investment Trust Agreement as a "Settlor"
and "CPO Holder," and (iii) if the transferring Securityholder is an Existing
Securityholder, be bound by the Security Trust Agreement as a "Grantor," and
prior to issuing any Company Securities to any Person, the Company (or, in the
case of the issuance of any CPOs to any Person, the NIT Trustee), shall cause
the prospective securityholder to sign a counterpart to this Agreement agreeing
to be bound as a "Securityholder" and an "Other Securityholder" under this
Agreement, unless otherwise determined by the Company and the Requisite
Investors; provided that to the extent that the Company issues any Series A
Shares or Series B Shares, the Company shall cause the holder thereof to be
deemed to be an "Existing Shareholder" under the Security Trust Agreement. Any
transferee of an Existing Securityholder shall be deemed to be an "Existing
Securityholder" hereunder, any transferee of an Other Securityholder shall be
deemed to be an "Other Securityholder" hereunder and any transferee of an
Investor shall be deemed to be an "Investor" hereunder. Each Securityholder
acknowledges that prior to issuing or registering the transfer of any CPOs to
any Person, pursuant to the Neutral Investment Trust Agreement, the NIT Trustee
shall cause the prospective CPO holder to sign a





                                     E-136
<PAGE>   16

counterpart to this Agreement and to the Neutral Investment Trust Agreement
unless otherwise determined by the NIT Trustee and the Requisite Investors.

          (h) Agreement Regarding Indirect Transfers. Notwithstanding the
foregoing, no Securityholder shall avoid the provisions of this Agreement by
first making a Transfer to a Permitted Transferee and then disposing of or
transferring all or any portion of such Securityholder's interest in any such
Permitted Transferee or by entering into any other transaction intended to avoid
the provisions of this Section 6. In addition, the provisions of this Section 6
shall apply to the Transfer of any beneficial interests, equity interests or
other ownership interests in any trust that holds Series A Shares or Series B
Shares and the permitted transferees and successors thereof that are entities,
assuming for purposes of this Section 6(h) that references to the "Company" in
this Section 6 are references to such trust and that references to a
"Securityholder" are references to the beneficiaries thereof.

          7. Regulatory Compliance; Conversions of Series N Shares and Series C
Shares.

          (a) Regulatory Compliance. Before the Company redeems, purchases or
otherwise acquires or takes any action with respect to the voting rights of any
of its shares (excluding a repurchase of Series N Shares or Series C Shares or
purchase of CPOs pursuant to Section 10 below), the Company shall give written
notice of such pending action to the Common Representative and each of the
Investors. Upon the written request of any Regulated Investor made within 10
days after its receipt of any such notice, the Company shall defer taking such
action for such period (not to extend for more than 45 days after the Common
Representative's and the Regulated Investor's receipt of the Company's original
notice) as the Regulated Investor requests to permit such Regulated Investor and
its Affiliates to obtain any requisite authorization to retain such Company
Securities or to otherwise reduce the quantity of such Company Securities it
owns in order to avoid the Regulatory Problem. If the Regulated Investor has a
Regulatory Problem, the Company and the Securityholders will cooperate and
assist such Regulated Investor by taking such actions as may be necessary or (in
the opinion of the Regulated Investor) desirable as requested by the Regulated
Investor to resolve such Regulatory Problem.

          (b) Conversion of Series N Shares and Series C Shares. At the request
of any Regulated Investor at any time (whether in connection with any action by
the Company referred to in Section 7(a) above or otherwise), such Regulated
Investor shall have the right, upon the occurrence or possible occurrence of a
Regulatory Problem to convert (without the delivery or payment by the NIT
Trustee or such Regulated Investor of any additional consideration) such number
of Series N Shares or Series C Shares then held (beneficially or of record) by
such Regulated Investor or CPOs held by such Regulated Investor and/or its
Affiliates which may be deemed to be voting shares under laws applicable to such
Regulated Investor into a like number of nonvoting shares (whether in the form
of Company Securities, preferred shares or other securities, as permitted by
Mexican law). In the event of such conversion, the Regulated Investor and/or its
Affiliates, as the case may be, shall be entitled to all the rights which they
had pursuant to this Agreement, the Subscription Agreement or any other
Transaction Agreement as a holder of (i) such Series N Shares, other than the
limited voting rights of such Series N Shares, (ii) such Series C Shares, other
than the mandatory voting in the same manner as the majority vote of the Series
A Shares, and (iii) such CPOs (if any). In addition, in the event such
Regulatory Problem ceases to exist or at the Regulated Investor's request at any
other time, the NIT Trustee and such Regulated Investor and its Affiliates shall
have the right to reconvert such other shares or securities into Series C Shares
and/or Series N Shares. In the event of a reconversion of any such shares or
securities into Series C Shares and/or Series N Shares, the electing
Securityholder agrees to deposit such Series C Shares and Series N Shares into
the Neutral Investment Trust in exchange for CPOs.

          (c) Subdivisions, Combinations, etc. If the Company in any manner
subdivides or combines the outstanding shares of one class or series of shares,
the outstanding shares of the other class or series of shares shall be
proportionately subdivided or combined in a similar manner.

          (d) Compliance with Applicable Laws. Notwithstanding anything to the
contrary in this Agreement, nothing in this Section 7 shall require the Company
to take any action that would cause the Company to forfeit or violate the terms
of any of its Mexican grants (concessions) to operate the Business or that would
cause the Company to violate applicable law, which violation of law would have a
material adverse effect on the Business, taken as a whole.

          8. Investor Liquidity Rights.




                                     E-137
<PAGE>   17

          (a) Retention of Investment Banker. If on or prior to May 21, 2002
(the fourth anniversary of the date of the Original Shareholders Agreement), the
Company has not for any reason completed a Qualified Public Offering, then the
Requisite Investors shall have the right (but not the obligation) from time to
time after such date (but no more frequently than one time in any 6-month
period) to cause the Existing Securityholders to select an investment banker
from among three investment bankers designated by the Requisite Investors (the
"Investment Banker") to assess the feasibility of consummating a Qualified
Public Offering at a price per share at least equal to the Offering Price. The
Company and the Existing Securityholders hereby agree to take (or cause to be
taken) all acts and execute all instruments as may be necessary or (in the
opinion of the Requisite Investors) desirable to enable the Requisite Investors
to retain (at the Company's expense) the Investment Banker.

          (b) Feasibility Determination. As soon as reasonably practicable after
the Investment Banker has been retained as provided above, the Investment Banker
will evaluate the condition of the U.S. and Mexican markets and of the Company
and will assess the feasibility (and shall be instructed to complete such
assessment no later than 90 days after its retention) of consummating a
Qualified Public Offering at an offering price per share to the public in excess
of the equivalent of U.S. $40.00 per CPO (or U.S. $20.00 per Series N Share and
U.S. $20 per Series C Share), on a fully diluted basis as of the date hereof as
adjusted for share splits, combinations, dividends, recapitalizations or similar
events (the "Offering Price").

          (c) Specific Qualified Public Offering. If the Investment Banker
determines as provided above that a Qualified Public Offering at the Offering
Price (a "Specified Qualified Public Offering") is feasible, then the
Securityholders agree to cause the Board to approve of such a Specified
Qualified Public Offering and the Company and the Existing Securityholders each
hereby agree to use (and to cause the Company's management to use) their
respective best efforts (and take (or cause to be taken) all necessary and
desirable actions or other actions reasonably requested by any Investor) to
consummate such a Specified Qualified Public Offering. If the Investment Banker
determines as provided above that a Qualified Public Offering is feasible but at
a price per CPO (or per Series C Share and Series N Share as the case may be)
below the Offering Price, then the Board may approve or disapprove of such a
Qualified Public Offering in its good faith judgment; provided, however, that if
such Qualified Public Offering would only involve the sale of Company Securities
held by the Investors, then the Requisite Investors shall have the right within
15 days after the Investment Banker's determination to approve of such Qualified
Public Offering and, after any such approval, the Securityholders shall cause
the Board to approve of such Qualified Public Offering (after such approvals, a
"Specified Qualified Public Offering") and the Company and the Existing
Securityholders each shall use (and shall cause the Board and the Company's
management to use) their respective best efforts (and take (or cause to be
taken) all necessary and desirable actions or other actions reasonably requested
by any Investor) to consummate such a Specified Qualified Public Offering.

          (d) Investor Rights. If at any time (or from time to time) after the
Investment Banker's determination of the feasibility of a Specified Qualified
Public Offering the Requisite Investors determine in their good faith judgment
that the Existing Securityholders and/or the Company's management are not using
their respective best efforts to consummate such a Specified Qualified Public
Offering, then the Requisite Investors shall be entitled to so notify the
Company by delivering written notice to the Company describing in reasonable
detail the alleged deficiencies and the proposed actions which should be taken
to consummate the Specified Qualified Public Offering (the "IPO Default
Notice"). If within 5 business days after the delivery of the IPO Default Notice
the Requisite Investors determine that the Existing Securityholders, the Board
and/or the Company's management have not used their respective best efforts to
begin acting on the proposals in the IPO Default Notice and otherwise to cause
the consummation of the Specified Qualified Public Offering, and are not
continuing such efforts, then (unless the Investment Banker delivers to the
Company within such 5 business-day period a letter stating that it believes that
the Existing Securityholders, the Board and the Company's management are using
such best efforts), at the request of the Requisite Investors, the
Securityholders will cause the Board to replace the Company's management with
personnel selected by the Requisite Investors and shall cause the Company's
management to act on the proposals in the IPO Default Notice and otherwise to
cause the consummation of the Specified Qualified Public Offering. If at any
time (or from time to time) after the delivery of such an IPO Default Notice,
but in no event earlier than 10 business days after the delivery of such IPO
Default Notice, the Requisite Investors determine in their good faith judgment
that the Existing Securityholders and/or the Company's management are not using
their respective best efforts to consummate such a Specified Qualified Public
Offering, then the Requisite Investors shall be entitled to so notify the
Company by delivering an additional IPO Default Notice to the Company. If the
Requisite Investors determine that the Existing Securityholders, the Board
and/or the Company's management have not, within 5




                                     E-138
<PAGE>   18

business days after the delivery of such IPO Default Notice, used their
respective best efforts to begin acting on the proposals in such IPO Default
Notice and otherwise to cause the consummation of the Specified Qualified Public
Offering, and are not continuing such efforts, then (unless the Investment
Banker delivers to the Company within such 5 business [ ] day period a letter
stating that it believes that the Existing Securityholders, the Board and the
Company's management are using such best efforts) the Requisite Investors shall
be entitled to exercise the voting rights of all Securityholders and to replace
the members of the Board pursuant to Section 1(e) (as contemplated by and in
accordance with the Security Trust Agreement) in order to cause such a Specified
Qualified Public Offering to be consummated by delivering written notice to the
Security Trust Trustee. The delivery of an IPO Default Notice shall not exhaust
the rights of the Requisite Investors to deliver additional IPO Default Notices,
and one or more subsequent IPO Default Notices may be given from time to time
thereafter containing modified or additional directions. The rights of the
Investors pursuant to this Section 8(d) are secured by the Security Trust
Agreement.

          (e) Sale Transaction if no Qualified Public Offering. If either:

          (i) the Investment Banker determined that a Specified Qualified Public
     Offering was feasible, but a Specified Qualified Public Offering has not
     occurred within 100 days following such determination, and the Company, the
     Existing Securityholders and/or the Company's management did not use their
     respective best efforts to consummate a Specified Qualified Public Offering
     and take all actions proposed in an IPO Default Notice; or

          (ii) for any reason no Qualified Public Offering has been consummated
     on or prior to May 21, 2005 (the seventh anniversary of the date of the
     Original Shareholders Agreement),

then the Requisite Investors shall have the right (but not the obligation) to
retain (at the Company's expense) an Investment Banker to consummate a Sale
Transaction (as defined below). In such event, the Company and all
Securityholders hereby agree to take (or cause to be taken) all actions and
execute all instruments as may be necessary or as may be requested by the
Requisite Investors to (i) enable the Investment Banker to conduct an auction in
an orderly process to maximize shareholder value and (ii) cause the Company
and/or the Securityholders to take (or cause to be taken) any of the following
actions or any combination thereof (collectively, "Sale Transactions"):

          (A)  selling all of the Company's and its subsidiaries' assets in one
               or more transactions;

          (B)  merging or consolidating the Company with or into any other
               Person;

          (C)  requiring that each Securityholder sell all of the Company
               Securities then held by such Securityholder; and/or

          (D)  requiring that each Securityholder sell all of the Company Shares
               then held by such Securityholder and each CPO Holder cause the
               NIT Trustee to sell all of the Company Shares that are part of
               the Neutral Investment Trust's trust estate.

The proceeds of each such Sale Transaction shall either be cash, Cash
Equivalents or Marketable Securities. The Investors' rights to cause a Sale
Transaction and the Existing Securityholders' obligations with respect to a Sale
Transaction are secured by the Security Trust Agreement.

          In connection with each Sale Transaction, each holder of Company
Shares shall (and each CPO Holder shall use its best efforts to cause the Series
N Shares held in the Neutral Investment Trust to) vote for, consent to and raise
no objections against such Sale Transaction. To the extent such power is not
exercised by the NIT Trustee, each CPO Holder shall cause the voting power of
their CPOs to be voted for (or to consent to) such Sale Transaction, and each
CPO Holder shall not raise any objections to such Sale Transaction. If the Sale
Transaction is structured as a (i) merger or consolidation, each holder of
Company Shares shall waive (and each CPO Holder shall use its best efforts to
cause to be waived) any dissenters' rights, appraisal rights or similar rights
in connection with such merger or consolidation or (ii) sale of Company Shares,
each Securityholder shall either (depending on the terms and conditions so
approved) (A) agree to sell all of its Company Securities and rights to




                                     E-139
<PAGE>   19

acquire Company Securities on the terms and conditions so approved or (B) agree
to sell all of its Company Shares and, to the extent that such Securityholder is
also a CPO Holder, use its best efforts to cause the NIT Trustee to sell all of
the Company Shares that are part of the Neutral Investment Trust's trust estate
on the terms and conditions so approved. Each Securityholder shall take all
necessary or desirable actions in connection with the consummation of the Sale
Transaction as requested by the Board. Notwithstanding the foregoing, the
obligations of the Securityholders with respect to a Sale Transaction are
subject to the satisfaction of the conditions specified in Section 8(g)(iii)
below.

          (f) Shareholder Vote. Each Securityholder hereby agrees to (and in the
case of the CPO Holders, to use its best efforts to cause the NIT Trustee to)
vote in favor of, consent to, sell its Company Securities in connection with,
waive any rights to dissent from or any other actions reasonably requested from
time to time by the Requisite Investors in connection with any Sale Transaction
proposed to be effected pursuant to Section 8(e). To the extent that such power
is not exercised by the NIT Trustee, each CPO Holder shall use its best efforts
to cause the voting power of their CPOs to be voted for (or to consent to) such
Sale Transaction, and each CPO Holder shall not raise any objections to such
Sale Transaction. Each Securityholder and the Company shall take (or use its
best efforts to cause to be taken) all action requested by the Requisite
Investors in connection with such proposed Sale Transaction (including using its
best efforts to obtain any required regulatory approvals). Without limiting the
generality of the foregoing, in connection with each Sale Transaction pursuant
to Section 8(e)(C) above: (i) (A) each Securityholder shall sell its Company
Securities to the purchaser(s) directed by the Requisite Investors, or (B) at
the sole option of the Requisite Investors, each other Securityholder shall sell
all of its Company Shares to the purchaser(s) directed by the Requisite
Investors and each CPO Holder shall use its best efforts to cause the NIT
Trustee to sell all of the Company Shares that are part of the Neutral
Investment Trust's trust estate to such purchaser(s), (ii) to the extent
applicable, the Company shall make the corresponding entries in its Share
Registry Book, (iii) to the extent applicable, the Common Representative shall
direct the NIT Trustee to make the corresponding entries in its CPO Registry
Book, and (iv) each Securityholder shall deliver (or cause to be delivered) to
the purchaser(s) the certificates representing the Company Securities sold
pursuant to Section 8(e).

          (g) Sale of the Company.

          (i) Each of the Company and the Securityholders shall notify the Board
     immediately if any person(s) or entity(ies) make(s) any proposal, offer,
     inquiry or contact with respect to any (a) merger, reorganization or
     consolidation, (b) acquisition or purchase of assets of, or any equity
     interest in, or any securities convertible into or exchangeable for an
     equity interest in, or (c) similar transaction or business combination
     involving, the Company.

          (ii) If the Board receives (as provided in clause (i) above) any bona
     fide written offer with respect to a Sale of the Company Transaction after
     which the Investors would receive at least the Required Minimum Return,
     then the Securityholders shall cause a meeting of the Company's
     shareholders to be held as promptly thereafter as possible for the purpose
     of approving or disapproving of such Sale of the Company Transaction. If
     the holders of at least 60% of the Company Shares (including, for purposes
     of such calculation, the shares represented by the CPOs (i.e., each CPO
     shall count as two Series N Shares (as adjusted for any stock splits or
     reverse-stock splits of the Series C Shares or Series N Shares) and
     excluding any Company Shares (and any CPOs) held directly or indirectly by
     the offeror(s) and its or their respective Affiliates) approve such Sale of
     the Company Transaction (whether or not entitled to vote thereon) (an
     "Approved Sale"), each holder of Company Shares, shall (and each CPO Holder
     shall use its best efforts to cause the Series N Shares held in the Neutral
     Investment Trust to) vote for (or cause to be voted for), consent to and
     raise no objections against such Approved Sale. To the extent such power is
     not exercised by the NIT Trustee, each CPO Holder shall use its best
     efforts to cause the voting power of their CPOs to be voted for (or to
     consent to) such Approved Sale, and each CPO Holder shall not raise any
     objections to such Approved Sale. If the Approved Sale is structured as a
     (i) merger or consolidation, then each holder of Company Securities shall
     waive (or in the case of a CPO Holder, use its best efforts to cause to be
     waived) any dissenters' rights, appraisal rights or similar rights in
     connection with such merger or consolidation or (ii) sale of Company
     Shares, then each Securityholder, shall either (depending on the terms and
     conditions so approved) agree to sell (A) all of its Company Securities and
     rights to acquire Company Securities on the terms and





                                     E-140
<PAGE>   20

     conditions so approved or (B) all of its Company Shares and, to the extent
     that such Securityholder is also a CPO Holder, cause the NIT Trustee to
     sell all of the Company Shares that are part of the Neutral Investment
     Trust's trust estate, on the terms and conditions so approved. Each
     Securityholder shall take (or cause to be taken) all necessary or desirable
     actions in connection with the consummation of the Approved Sale as
     requested by the Board.

          (iii) The obligations of the holders of Company Securities with
     respect to the Approved Sale of the Company are subject to the satisfaction
     of the following conditions: (i) each shareholder, including the NIT
     Trustee, shall receive in exchange for the Company Shares held by it the
     same portion of the aggregate consideration from such sale or exchange that
     such shareholder would have received if such aggregate consideration had
     been distributed by the Company in complete liquidation pursuant to the
     rights and preferences set forth in the Company's By-laws as in effect
     immediately prior to such sale or exchange and (ii) if any CPO Holders or
     any holders of a series or class of Company Shares are given an option as
     to the form and amount of consideration to be received, each CPO Holder or
     holder of such series or class shall be given the same option.

          (iv) Notwithstanding anything to the contrary, (A) the CPO Holders and
     the NIT Trustee will only be required to make affirmative representations
     and warranties as to due power and authority, non-contravention and
     ownership of Company Securities, free and clear of all liens, and (B) the
     CPO Holders shall be severally obligated to join on a pro rata basis (based
     on each such CPO Holder's share of the aggregate proceeds paid with respect
     to its interest) in any indemnification obligation that the other
     Securityholders of the Company (other than the NIT Trustee) have agreed to
     in connection with such Approved Sale other than any such obligations that
     relate specifically to a particular Securityholder, such as indemnification
     with respect to representations and warranties given by a Securityholder
     regarding such Securityholder's title to and ownership of shares; provided
     that no such holder shall be obligated in connection such Approved Sale to
     indemnify the prospective transferee or its affiliates with respect to an
     amount in excess of the net cash proceeds paid to such holder in connection
     with such Approved Sale; provided further that any escrow of proceeds of
     any such transaction shall be withheld on a pro rata basis among all
     Securityholders; and provided further that notwithstanding the foregoing,
     the NIT Trustee shall not be obligated to join in any indemnification
     obligation that the Securityholders may agree to in connection with such
     Approved Sale.

          (h) Preference Upon Sale of the Company. The Company and each
Securityholder agree that in the event of any sale or exchange by the
Securityholders of all or substantially all of the Company Shares and other
equity securities of the Company (whether by sale, merger, recapitalization,
reorganization, consolidation, combination or otherwise and whether or not
pursuant to this Section 8), each shareholder, including the NIT Trustee, shall
receive in exchange for the Company Shares and other equity securities of the
Company held by such shareholder the same portion of the aggregate consideration
from such sale or exchange that such shareholder would have received if such
aggregate consideration had been distributed by the Company in complete
liquidation pursuant to the rights and preferences set forth in the Company's
By-laws as in effect immediately prior to such sale or exchange, and each
agreement or other document effecting or evidencing such sale or exchange shall
reflect such preference and shall require the disbursement of proceeds in
accordance therewith. Each Securityholder shall take (or use its best efforts to
cause to be taken) all necessary or desirable actions in connection with the
distribution of the aggregate consideration from such sale or exchange as
requested by the Requisite Investors.

          9. Investor Registration Rights.

          (a) In addition to all other rights and remedies of the Investors
under this Agreement, after May 21, 2002 (the fourth anniversary of the date of
the Original Shareholders Agreement), the Requisite Investors may request that
the Company take all requisite actions at the Company's expense to permit the
Investors to sell the Company Securities held by them pursuant to an initial
public offering under (i) applicable Mexican securities laws, rules and
regulations and/or (ii) applicable United States federal and state securities
laws and, in either such event, the Company shall be obligated to become, and
each Securityholder hereby agrees to take (or cause to be taken) all actions
necessary or requested by the Securityholders to cause the Company to become, a
public company under





                                     E-141
<PAGE>   21

such laws and to enable such holders to freely transfer their securities
(including the CPOs) in the appropriate market without any securities laws or
other restrictions, as soon as possible after such request. In addition, in
connection with any secondary offering of the Company's Securities, the
Investors will be entitled to participate in such secondary offering prior to
any other holder of Company Securities. In furtherance thereof, each
Securityholder agrees that the Requisite Investors shall have the right to
demand that the Company's Securities (at the Company's expense) be registered at
the National Registry of Securities and Intermediaries of the National Banking
and Securities Commission of Mexico and sell the Investors' Company Securities
in connection with any such public offering and, upon such demand, the Company
shall take all such actions to enable the Investors to sell their securities
(including the CPOs) in a Public Sale, or otherwise freely transfer their
securities (including the CPOs) without restrictions, in accordance with the
Mexican securities laws and/or United States federal or state securities laws.
The Company for this purpose shall assist each Investor in connection with such
Public Sale and shall furnish all information which such Investor or the
managing underwriters deem necessary or desirable to be disclosed in any
prospectus to be distributed in connection with a Public Sale. If a primary or
secondary offering is an underwritten offering and the managing underwriters
advise the Company in writing that in their opinion the number of securities
(whether shares and/or CPOs) requested to be included in such offering exceeds
the number of such securities which can be sold therein without adversely
affecting the marketability of the offering, the Company will include in such
registration (i) first, the number and type of securities requested by the
Investors to be included which in the opinion of such underwriters can be sold
without adverse effect pro rata among the Investors on the basis of the number
of securities (including CPOs) held by each such Investor and (ii) second, other
shares requested to be included, pro rata among the holders of such shares on
the basis of the number of shares held by each such holder.

          (b) If so requested by the underwriters managing any such offering, no
holder of Company Securities shall sell any such securities during the seven
days prior to and the 90-day period beginning on the effective date of any
registered public offering under the securities laws of Mexico or the United
States, provided, however, that such lock-up period shall only apply to the type
and class of Company Securities included in such public offering unless the
underwriters managing such offering specifically require the extension of the
scope of such a lock-up to include additional classes or types of Company
Securities. Notwithstanding the foregoing, no CPO Holder shall be subject to any
lock-up agreement containing any prohibitions or other terms (e.g., length of
the lock-up) that are more onerous than those applicable to (i) any of the
Company Securities being offered to the public pursuant to such registered
public offering or (ii) any other holder of more than five percent (5%) of the
Company Securities.

          (c) For purposes of this Section 9 only, the term "Investor" shall
include CTGT and each CTGT Affiliated Securityholder with respect to its CPOs
only.

          10. Remedies Upon Event of Noncompliance.

          (a) Redemption Notice. If there occurs an Event of Noncompliance, then
(in addition to all other rights and remedies available at law or in equity),
each of the Investors shall have the right (but not the obligation) to deliver a
notice to the Company and the other Investors (the "Redemption Notice")
indicating that it intends to request that the Company redeem (with respect to
any Company Shares) or purchase (with respect to any CPOs) for cash (the
"Redemption Right") all (but not less than all) of the Company Shares and CPOs
held by such Investor (the "Redeemed Securities"). Upon receipt of the
Redemption Notice, the other Investors may elect to also request that the
Company redeem or purchase their respective Redeemed Securities by giving
written notice to the Investor who delivered the Redemption Notice and the
Company within 30 days after delivery of the Redemption Notice. All Investors
exercising the Redemption Right hereunder are collectively referred to herein as
the "Redeeming Investors."

          (b) Redemption Price. Upon the delivery of each Redemption Notice, the
Redeeming Investors and the Company shall have a period of 60 days to determine
the Redemption Price (as defined below). If such Redeeming Investors and the
Company are unable to determine the Redemption Price hereunder within 15 days
after delivery of the Redemption Notice, such Redeeming Investors shall select
an independent appraiser from the list of investment banks attached hereto as
Exhibit D or, if no such investment bank is available, shall select an
investment bank of recognized standing in the Mexican and international markets
experienced in the valuation of such business (a "Qualified Appraiser"), to
calculate (at the Company's expense) the Redemption Price in




                                     E-142
<PAGE>   22

accordance with the provisions of this Section 10, which Qualified Appraiser
shall be instructed to determine the Redemption Price within 45 days after the
expiration of such 15-day period and whose determination of the Redemption Price
shall be final and binding. The purchase price for each Redeemed Security (the
"Redemption Price") shall be the greater of (i) the Redemption Formula Price and
(ii) Fair Market Value per Redeemed Security as determined by the Qualified
Appraiser, but in no event less than the amount which would be distributable in
respect of such Redeemed Securities pursuant to the Company's By-laws upon a
liquidation and dissolution of the Company (assuming for such purpose with
respect to the purchase by the Company of any CPOs, the amount which would be
distributable in respect of the number of Series C Shares and Series N Shares
represented by such CPOs upon a liquidation an dissolution of the Company).

          (c) Redemption Right. Upon determination of the Redemption Price, each
Redeeming Investor shall have the right (but not the obligation) to request that
Company exercise the Redemption Right for the Redeemed Securities held by such
Redeeming Investor by delivering written notice to the Company and the other
Redeeming Investors (the "Redemption Notice"). If the Company desires to elect
to purchase all of the Redeemed Securities of all electing Redeeming Investors,
it shall in good faith deliver a notice to each Redeeming Investor committing to
purchase such shares (the "Commitment") within 30 days after the delivery of the
Redemption Notice. If the Company delivers the Commitment within such 30-day
period, the closing of such purchase (the "Redemption Closing") shall take place
within 120 business days after the delivery of the initial Redemption Notice
delivered after such Redemption Price determination (provided that the Company
shall have the right to extend such 120-day period by an additional 60 days by
delivering to the Redeeming Investors (pro rata based on the number of Redeemed
Shares held by all Redeeming Investors) a nonrefundable cash deposit (the
"Deposit") equal to 25% of the Redemption Price (which will be forfeited in full
if the Company fails for any reason to consummate the Redemption Closing and pay
the remainder of the Redemption Price in cash on or before the end of such
60-day period)). At the Redemption Closing, the Company shall make the
corresponding entries in its Share Registry Book (or in the case of CPOs, the
Common Representative shall direct the NIT Trustee to make the corresponding
entries in the CPO Registry Book), the Redeeming Investors shall deliver to the
Company (or in the case of CPOs, to the Trustee) certificates representing the
Redeemed Securities, and the Company (or its designees, including any holder of
Series A Shares or Series B Shares) shall deliver to the Redeeming Investors the
aggregate Redemption Price for the Redeemed Securities by wire transfer of
immediately available funds to accounts designated by the Redeeming Investors.
If the Company does not deliver the Commitment to purchase all of the Redeemed
Shares within the 30-day period in accordance with the foregoing, or if the
Company elects to purchase the Redeemed Securities but fails to consummate the
Redemption Closing within such 120-day period (or 180-day period, as applicable)
(each, a "Call Trigger Event"), then each Investor shall retain any Deposit and
have the rights set forth in Section 11 below. Notwithstanding anything to the
contrary in this Section 10, despite any request by the Company for an extension
for an additional 60 days pursuant to the foregoing, unless the Company shall
have paid to the Redeeming Investors, and the Redeeming Investors shall have
received, the Deposit, a Call Triggering Event shall be deemed to have occurred
upon the expiration of such 120-day period.

          11. Call Rights.

          (a) Call Notice. If for any reason there occurs a Call Trigger Event,
then the Requisite Investors shall have the right (but not the obligation) to
require the Existing Securityholders to sell (the "Call") to all electing
Investors (and/or their respective nominees or assignees) all (but not less than
all) of the Company Securities held by the Existing Securityholders (the "Call
Securities"), by delivering a written notice to the Company within 60 days after
a Call Triggering Event has occurred (which the Company shall then deliver to
all other Investors and the Existing Securityholders) (the "Call Notice"). The
obligation of the Existing Securityholders to perform the Call is referred to
herein as the "Call Obligation" and the failure of any of the Existing
Securityholders to fulfill its Call Obligation is referred to herein as a "Call
Default." The Call Obligation is secured by the Security Trust Agreement. Those
Investors who originally delivered the Call Notice and any other Investor who
has subsequently elected in writing within 10 days thereafter to participate in
the Call shall be deemed to be "electing Investors" for purposes of this Section
11.

          (b) Call Closing. Upon the delivery of the Call Notice, the electing
Investors (and/or their respective nominees or assignees) shall purchase and the
Existing Securityholders shall sell the Call Securities (the "Call Closing") on
the date specified in the Call Notice, but in no event more than 180 days after
delivery of the Call Notice, and at the Call Price (as defined below). If the
Existing Securityholders fail to deliver the Call Securities as





                                     E-143
<PAGE>   23

specified, the electing Investors shall be entitled to instruct the Security
Trust Trustee to deliver such Company Securities hereunder pursuant to the
Security Trust Agreement. At the Call Closing, the Company shall make the
corresponding entries in its Share Registry Book, the Existing Securityholders
shall direct the NIT Trustee under the Security Trust Agreement to deliver to
the electing Investors certificates representing the Company Shares to be
purchased by the electing Investors, and the electing Investors shall deliver to
the Existing Securities the aggregate Call Price for the Call Securities by wire
transfer of immediately available funds to an account designated by each of the
Existing Securityholders.

          (c) Call Price. The purchase price for each Call Share (the "Call
Price") shall be the Fair Market Value per Call Security (i) as determined using
the most recent valuation by a Qualified Appraiser pursuant to Section 10 or
(ii) in the event that more than 3 months have elapsed since the date of such
valuation or, in the event of a material adverse change in the Company's
business, as determined by the Qualified Appraiser selected in accordance with
Section 10, whose determination shall be made within 45 days thereafter and
whose determination of the Call Price shall be final and binding.

          12. Miscellaneous.

          (a) U.S. GAAP. In calculating the Redemption Price, the Call Price and
any other calculations and determinations under this Agreement, all accounting
determinations shall be made in accordance with United States generally accepted
accounting principles, consistently applied in the preparation of the Company's
audited financial statements.

          (b) Tax Planning. Each Securityholder hereby agrees that in the event
of an exercise of the Redemption Right, a Sale Transaction or the Call, it will
cooperate and use commercially reasonable efforts to structure the applicable
purchase and sale so as to optimize the tax planning of all parties involved in
accordance with applicable U.S., Mexican and other laws.

          13. Definitions.

          "Affiliate" of any Person means any other Person controlling,
controlled by or under common control with such particular Person, and "control"
means the possession, directly or indirectly, of the power to direct the
management and policies of a Person, whether through the ownership of voting
securities, contract or otherwise. For purposes of this Agreement and the other
Transaction Agreements, each of BAIIC and LA Strategic Capital Partners II shall
be deemed to be an "Affiliate" of the other.

          "BAIIC Investors" means, collectively, BankAmerica International
Investment Corporation ("BAIIC"), LA Strategic Capital Partners II, Edward
McCaffrey, and their respective successors and permitted assigns and permitted
transferees.

          "Bachow Investors" means, collectively, Bachow Investment Partners
III, LP ("BIP"), Bachow & Associates, Inc., each of the limited partners of BIP,
the general partner of BIP (and its limited partners and general partners), the
direct and indirect equity holders of any thereof, and their respective
successors and permitted assigns and permitted transferees. In furtherance and
not limitation of the foregoing, Bachow Investors includes Paul S. Bachow,
Salvatore A. Grasso and Jay D. Seid. If the Bachow Investors consist of more
than one Person, all decisions hereunder made on behalf of the Bachow Investors
shall be made by, or in accordance with written instructions delivered to the
Company by Bachow & Associates, Inc., irrespective of any notice to the contrary
from any other Person.

          "Baseline Plan" means the strategic business plan and budget attached
hereto as Exhibit E.

          "Bureau" means the General Bureau of Foreign Investment of the
Ministry of Commerce and Industrial Development.





                                     E-144
<PAGE>   24

          "Business" means the business of providing local, long distance and
network telecommunications services in Mexico pursuant to concessions and/or
permits issued by the Mexican government and the sale or rental of related
equipment to subscribers of such services.

          "Cash Equivalents" means (a) marketable direct obligations issued or
unconditionally guaranteed by the United States government or issued by any
agency thereof and backed by the full faith and credit of the United States in
each case maturing within one year from the date of acquisition thereof, (b)
commercial paper maturing no more than one year from the date issued and, at the
time of acquisition, having a rating of at least A-1 from Standard & Poor's
Corporation or at least P-1 from Moody's Investors Services, Inc., (c)
certificates of deposit or bankers' acceptances maturing within one year from
the date of issuance thereof issued by, or overnight reverse repurchase
agreements from, any commercial bank organized under the laws of the United
States of America or any state thereof or the District of Columbia having
combined capital and surplus of not less than U.S. $250,000,000 and not subject
to setoff rights in favor of such bank, (d) time deposits maturing no more than
thirty days from the date of creation thereof with commercial banks having
membership in the United States Federal Deposit Insurance Corporation in amounts
not exceeding the lesser of U.S. $100,000 or the maximum amount of insurance
applicable to the aggregate amount of the Company's deposits at such institution
and (e) deposits or investments in mutual or similar funds offered or sponsored
by brokerage and other companies having membership in the Securities Investor
Protection Corporation in amounts not exceeding the lesser of U.S. $100,000 or
the maximum amount of insurance applicable to the aggregate amount of the
Company's deposits at such institution.

          "Company Shares" means the Company's (i) nominative, series A shares
with full voting rights, no par value and which may only be held by Mexican
individuals or Mexican entities with a clause in their by-laws prohibiting
foreign ownership ("Series A Shares"); (ii) nominative series B shares with full
voting rights, no par value and which may be held by Mexican and foreign
individuals or corporations ("Series B Shares"), (iii) nominative Series C
shares with full voting rights and no par value (the "Series C Shares"), and
(iv) nominative series N shares with limited voting rights and no par value
("Series N Shares").

          "Company Securities" means the Company Shares and the CPOs.

          "CPOs" means the Ordinary Non-redeemable Participation Certificates
issued by the NIT Trustee pursuant to the Neutral Investment Trust Agreement,
each representing the economic rights of one Series C Share and one Series N
Share, the limited voting rights of one Series N Share and the other rights
under the terms of the Neutral Investment Trust Agreement.

          "CTGT Affiliated Securityholder" means any of L.D. Coltrane, III,
Michael R. Coltrane, Samuel E. Leftwich and Thomas A. Norman, and any Person to
whom any CTGT Affiliated Securityholder transfers any Company Securities in
accordance with the terms of this Agreement.

          "EBITDA" means, for any period of the Company and its subsidiaries,
the consolidated net income (loss) of the Company and its subsidiaries for such
period plus, without duplication, (i) an amount equal to any extraordinary loss
of the Company and its subsidiaries (to the extent such loss was deducted in
computing such net income (loss), (ii) provision for taxes based on income or
profits of the Company and its subsidiaries for such period (to the extent such
provision for taxes was included in computing such net income (loss), (iii)
consolidated net interest expense of the Company and its subsidiaries for such
period (including amortization of debt issuance costs) to the extent that any
such expense was deducted in computing such net income (loss), (iv) the amount
of any fees paid or accrued by the Company and its subsidiaries to or on behalf
of BIP and/or CT Global Telecommunications, Inc. during such period (to the
extent that any such fees were deducted in computing such net income (loss)),
(v) depreciation, amortization (including amortization or goodwill and other
intangibles), other non-cash charges and expenses of the Company and its
subsidiaries for such period to the extent that such depreciation, amortization
and other non-cash charges or expenses were deducted in computing such net
income (loss) for such period and (vi) net income (loss) of the Company and its
subsidiaries not generated from the operation of the Business in the ordinary
course for such period, in each case on a consolidated basis, determined in
accordance with United States generally accepted accounting principles and as
reflected on the Company's and its subsidiaries' audited financial statements
for the most recent fiscal year delivered to the Investors pursuant to Section
5(a) above.




                                     E-145
<PAGE>   25

          "Engagement Letter" means that certain Engagement Letter dated
November 13, 1997 as amended on March 13, 1998 and April 2, 1998 between the
Company and Amsterdam Pacific LLC.

          "Event of Noncompliance" means the following events have occurred: (a)
a breach (a "Breach") by the Company or any of the Existing Securityholders of
any of the provisions of Section 2A(a) (indebtedness), 2A(b) (equity issuances),
2A(c) (assets sales, mergers, etc.), 2A(d) (bankruptcy, etc.), 2A(h) (key
employees), 2A(i) (Approved Plan), 2A(j) (new businesses), 2A(n) (commitments),
5 (other than Section 5(c) only with respect to the period ending May 21, 2002
(the fourth anniversary of the date of the Original Shareholders Agreement)),
and 6; and (b) the Requisite Investors provided written notice to the Company
describing in reasonable detail the Breach and proposed cure (the "Breach
Notice"); and (c) the Company and/or the applicable Existing Securityholders
shall have failed to cure any such Breach (if curable) within 30 days after
delivery of such Breach Notice (as determined to the satisfaction of the
Requisite Investors); provided that, with respect to any Breach other than of
Section 5(a), if at the end of such 30-day period the Company and the Existing
Securityholders are diligently taking all necessary actions to cure such Breach,
then such Breach shall not become an Event of Noncompliance unless not cured
within 60 days after delivery of such Breach Notice; provided further that in no
event shall any cure periods contained in this definition be longer than the
cure period for such action, event or condition applicable in any other
agreement binding upon the Company. The parties hereto agree that despite any
ruling or determination that an agreement, obligation, provision or covenant
herein is unenforceable for any reason under applicable law, the breach or
failure to adhere to such agreement, obligation, provision or covenant shall
nevertheless constitute a Breach hereunder.

          "Fair Market Value" means the value per applicable Company Security
(i.e., per share or per CPO) which such Company Security would receive upon a
sale of the Company at fair market value, determined on a going concern basis as
between a willing buyer and a willing seller and taking into account all
relevant factors determinative of value (but not taking into account any
discounts for lack of liquidity or voting rights, minority position or other
similar or related discounts), as determined by a Qualified Appraiser.

          "Family Group" means a Person's spouse, parents, siblings and
descendants (whether natural or adopted) and any trust solely for the benefit of
the Securityholder and/or the Securityholder's spouse and/or descendants.

          "Guidelines" means the Company Guidelines attached hereto as
Exhibit F.

          "Marketable Securities" means securities that are (i) listed or quoted
on a United States national securities exchange or quoted on a United States
national automated inter-dealer quotation system, (ii) eligible for sale by the
distributee (assuming that the distributee is not an affiliate of the issuer of
such securities) pursuant to a registration statement effective under the
Securities Act of 1933, as amended, or pursuant to Rule 144(k) of the Securities
Act of 1933, as amended, or any similar provision then in force and (iii) issued
by issuers with total assets of at least U.S. $250,000,000.

          "Mexico" means the United Mexican States.

          "Neutral Investment Trust" means that certain Irrevocable Neutral
Investment Trust established pursuant to the Neutral Investment Trust Agreement.

          "Neutral Investment Trust Agreement" means that certain Irrevocable
Neutral Investment Trust Agreement, No. 14515/5, dated as of August 18, 2000,
among the Company, the settlors thereunder, and the NIT Trustee, as amended and
modified from time to time in accordance with its terms.

          "Nissho Credit Agreement" has the meaning set forth in the fourth
Whereas clause of this Agreement.

          "Nissho Iwai" means Nissho Iwai American Corporation, a New York
corporation.

          "Nissho Stock Option Agreement" means that certain Stock Option
Agreement, dated March 24, 1998 between the Company and Nissho Iwai.





                                     E-146
<PAGE>   26

          "Nissho Trust" has the meaning set forth in the fourth Whereas clause
of this Agreement.

          "NIT Trustee" means, with respect to the Neutral Investment Trust
Agreement, Banco Nacional de Mexico, S.A., Institucion de Banca Mdltiple, Grupo
Financiero Banamex Accival, Division Fiduciaria, and any replacement or
successor trustee thereunder.

          "Operating Agreements" means that certain Amended and Restated
Operating Agreement, dated May 21, 1998, between the Company and CT Global
Telecomunicaciones, Inc.

          "Participation Agreement" means that certain Agreement Regarding
Participation and Registration Rights, dated May 21, 1998, among the Company, CT
Global Telecommunications, Inc., Grupo Empresarial de Telecomunicaciones, S.A.
de C.V., and Trust F/6404.

          "Person" means an individual, a partnership, a corporation, a limited
liability company, an association, a joint stock company, a trust, a joint
venture, an unincorporated organization and a governmental entity or any
department, agency or political subdivision thereof.

          "Public Sale" means any sale of Company Securities to the public (a)
pursuant to an offering registered under the Mexican securities laws and/or the
United States securities laws in accordance with the registration statement
covering such Company Shares or (b) through a broker, dealer or market maker
pursuant to the provisions of Rule 144 (or similar provision then in force)
adopted under the United States securities laws.

          "Qualified Affiliate" of any Person means (i) any other Person 90% or
more of whose equity and other voting securities are beneficially owned by such
Person or (ii) any other Person who beneficially owns 90% or more of the equity
and other voting securities of such Person (it being understood that,
notwithstanding the foregoing, BAIIC and LA Strategic Capital Partners II shall
be deemed to be "Qualified Affiliates").

          "Qualified Public Offering" means the consummation of an underwritten
initial public offering (whether a primary or a secondary offering) registered
under the Mexican securities laws, rules or regulations or the United States
Securities Act of 1933, as amended, of the Company's CPOs (or other freely
transferable securities into which CPOs are convertible without the delivery or
payment by any CPO Holder of any additional consideration and which give full
liquidity to the CPOs) yielding aggregate net proceeds to the Company of at
least U.S. $50,000,000 (which Qualified Public Offering, as of the date hereof,
would require the Company to list on a Mexican exchange the CPOs and/or on a
U.S. exchange "ADRs" consisting of such CPOs).

          "Redemption Formula Price" of any Company Share means a fraction, (A)
the numerator of which shall be the sum of (1) the product of (x) the Company
and its subsidiaries' EBITDA for the immediately preceding fiscal year and (y)
nine plus (2) the amount of cash and cash equivalents (including Cash
Equivalents and Marketable Securities) less the amount of principal and interest
owing in respect of indebtedness for borrowed money of the Company and its
subsidiaries and (B) the denominator of which shall be the number of Company
Shares then outstanding, in each case as shown on the audited financial
statements of the Company and its subsidiaries for the most recent fiscal year
delivered to the Investors pursuant to, and in accordance with Section 5(a). The
Redemption Formula Price of a CPO shall be equal to two times the Redemption
Formula Price of a Company Share.

          "Regulated Investor" means BAIIC, BancBoston and any other Investor
which is subject to regulation under the U.S. Bank Holding Company Act, as
amended (including, without limitation, Regulation K).

          "Regulation K" means Regulation K promulgated by the U.S. Federal
Reserve Bank under the U.S. Bank Holding Company Act, as amended.

          "Regulatory Problem" means any transaction, circumstance or situation
whereby (A) any Regulated Investor and its Affiliates would own (beneficially or
of record), control or have power over a greater quantity of securities of any
kind issued by the Company or any other entity than are permitted under any
requirement of any governmental authority, or (B) any governmental regulatory
agency is then asserting (or such




                                     E-147
<PAGE>   27

Regulated Investor believes that there is a risk of such assertion) that such
Regulated Investor and its Affiliates are not entitled to hold, or exercise any
significant right with respect to, the Company Securities held by such Regulated
Investor.

          "Required Minimum Return" means, as determined by the Requisite
Investors, a Sale of the Company Transaction in any given year that yields (in
cash, Cash Equivalents or Marketable Securities) a minimum return to the
Investors (equal to the multiple specified below multiplied by the aggregate
amount of cash paid by the Investors to purchase the Company Securities held by
them) as specified below:

<TABLE>
<CAPTION>
               Year of Sale                        Minimum Multiple
               ------------                        ----------------
               <S>                                 <C>
                   2000                                  3.0x
                   2001                                  4.0x
           2002 and thereafter                           5.0x
</TABLE>


          "Requisite Investors" means the holders of at least sixty percent
(60%) of the CPOs originally issued to (a) the Investors pursuant to the Neutral
Investment Trust Agreement on the date hereof and (b) Latinvest Strategic
Investment Fund, L.P. pursuant to the Neutral Investment Trust Agreement on the
date hereof, all such holders of the CPOs specified in clauses (a) and (b) above
voting together as a separate class for purposes of this Agreement.

          "Sale of the Company Transaction" means any transaction or series of
related transactions with any independent third party(ies) involving (a) a
merger, reorganization or consolidation, (b) an acquisition or purchase of
assets of, or any equity interest in, or any securities convertible into or
exchangeable for an equity interest in, or (c) similar transaction or business
combination involving, the Company, after which (i) 50% or more of the total
equity shares (on a fully diluted basis) or consolidated assets of the Company
would be sold and (ii) the Investors would have received at least the Required
Minimum Return.

          "Security Trust Agreement" means that certain Amended and Restated
Irrevocable Administration and Security Trust Agreement, dated as of August 18,
2000, among the Company, the Investors, the Existing Securityholders and
Bancomer, S.A., Institucion de Banca Multiple, Grupo Financiero Bancomer,
Direccion Fiduciaria, as trustee, as amended and modified from time to time in
accordance with its terms.

          "Security Trust Trustee" means, with respect to the Security Trust
Agreement, Bancomer, S.A., Institucion de Banca Multiple, Grupo Financiero
Bancomer, Direccion Fiduciaria, and any replacement or successor trustee
thereunder.

          "Strategic Assistance Agreement" means that certain Strategic
Assistance Agreement, dated May 21, 1998, between the Company and Bachow &
Associates.

          "Transaction Agreements" means (i) the Subscription Agreement, (ii)
the By-laws, (iii) this Agreement, (iv) each of the Confidentiality and
Non-Compete Agreements (as defined in the Subscription Agreement), (v) the
Security Trust Agreement, (vi) the Strategic Assistance Agreement, (vii) each of
the employment agreements contemplated by Section 5(l) of the Original
Shareholders Agreement, (viii) the Operating Agreement, (ix) the Participation
Agreement, (x) the Guidelines, (xi) the Management Option Plan (as defined in
the Subscription Agreement), (xii) the Engagement Letter, (xiii) the Nissho
Stock Option Agreement, and (xiv) each of the other agreements contemplated
hereby and thereby. In addition, Transaction Agreements shall also include the
Neutral Investment Trust, the Security Trust Agreement and the Capital
Contribution Agreement dated March 8, 2000, among the Company and certain of its
shareholders and their affiliates. Transaction Agreements shall include, to the
extent applicable, each Transaction Agreement as such agreement may be amended
from time to time in accordance with its terms and this Agreement.
Notwithstanding the foregoing, the Transaction Agreements do not include the
Nissho Trust or the Nissho Credit Agreement.



                                     E-148
<PAGE>   28

          "Transfer" with respect to any interest means the sale, transfer,
assignment, pledge or other disposition of (whether with or without
consideration and whether voluntarily or involuntarily or by operation of law)
any such interest.

          14. Share Certificate Notation.

          (a) The Company's share certificates for all of its shares (including
any shares held by the NIT Trustee and the Security Trust Trustee) shall bear
the following legend and any other legend required by the Board and the
Requisite Directors:

          The shares represented by this certificate are subject to the
          restrictions specified herein and in the Amended and Restated
          Securityholders Agreement, dated as of August 18, 2000, as amended and
          modified from time to time, a copy of which is on file at the
          Company's offices."

          (b) The Company shall place the legend described in subsection (a)
above on each and every certificate evidencing Company Shares outstanding as of
the date hereof, including any certificate evidencing Company Shares that was
issued prior to August 18, 2000. The legend set forth above in subsection (a)
shall be removed from the certificates evidencing any Company Shares upon their
Transfer in a Public Sale. The Common Representative shall direct the NIT
Trustee to include a similar legend on each certificate evidencing a CPO.

          (c) The Company shall register this Amended and Restated
Securityholders Agreement (and any amendments hereto) in its head office, shall
enter into the Shareholders' Registry Book a notation acceptable to the Board
and the Requisite Directors, shall certify to the Securityholders that such
notation has been made to the Shareholders' Registry Book and shall comply fully
with the obligations undertaken herein.

          (d) The Common Representative shall maintain a copy of this Amended
and Restated Securityholders Agreement (and any amendments hereto) in its
office, and shall direct the NIT Trustee to enter into the CPO Registry Book a
notation acceptable to the Board and the Common Representative, shall certify to
the CPO Holders that such notation has been made to the CPO Registry Book and
shall comply fully with the obligations undertaken herein.

          15. Amendment and Waiver.

          (a) Except as otherwise expressly provided herein, no modification,
amendment or waiver of any provision of this Agreement shall be effective
against the Company or the Securityholders unless such modification, amendment
or waiver is approved in writing by the Company, the holders of a majority of
the CPOs, the Requisite Investors, the holders of a majority of the Series A
Shares and the holders of a majority of the Series B Shares, in each case voting
as a separate class; provided that in the event that any such modification,
amendment or waiver would materially and adversely affect the rights or
obligations of a holder or group of holders of Company Securities in a manner
different than any other holders of Company Securities, then such modification,
amendment or waiver will require the consent of such holder of Company
Securities or a majority of the Company Securities held by such group of holders
materially and adversely affected.

          (b) Each of the Securityholders hereby acknowledges and agrees that
this Agreement is not intended to (i) adversely affect in any manner the rights
granted to the holders of the Series N Shares under the Original Shareholders
Agreement (the "Prior Rights") or (ii) amend any of the rights or obligations of
the Securityholders under the Original Shareholders Agreement except to the
extent expressly set forth herein. In the event of any ambiguities between the
rights and obligations of the Securityholders under this Agreement and their
rights and obligations as Company shareholders under the Original Shareholder
Agreement (as determined by the Requisite Investors), at the request of the
Requisite Investors, each of the Securityholders agrees to first use their best
efforts and negotiate in good faith to amend this Agreement to preserve the
Prior Rights and respective obligations that each Company Securityholder had as
a Company shareholder under the Original Shareholders Agreement. Furthermore, in
the event of a conflict among the relative rights and obligations of the
Securityholders in the context of resolving an ambiguity between the rights and
obligations of the Securityholders under this




                                     E-149
<PAGE>   29

Agreement and their rights under the Original Shareholders Agreement, each
Securityholder agrees and consents that such conflict shall be resolved in the
manner which least adversely affects the Prior Rights.

          16. Successors and Assigns. Subject to the restrictions on transfer
set forth in Section 6, this Agreement and each of the rights and obligations
hereunder shall bind and inure to the benefit of and be enforceable by the
Securityholders and any subsequent holders of Securities and their respective
successors and assigns, and shall be binding upon the Company and it successors
and assigns. In addition, whether or not any express assignment has been made,
unless otherwise expressly provided herein, the provisions of this Agreement
which are for any Securityholder's or Investor's benefit as a holder of
Securities are also for the benefit of, and enforceable by, any subsequent
holder of such Securities (provided that such subsequent holder has acquired
such Securities in accordance with the provisions of this Agreement, including
Section 6 above).

          17. Counterparts. This Agreement may be executed in multiple
counterparts (including by means of telecopied signature pages), each of which
shall be an original and all of which taken together shall constitute one and
the same agreement.

          18. Notices.

          (a) Any notice provided for in this Agreement shall be in writing and
shall be either personally delivered, sent by reputable overnight courier
service (charges prepaid) or sent by facsimile and followed with a copy sent by
a reputable overnight courier (charges prepaid) to the Company and any other
recipient at the address indicated on the signature pages hereto and to any
subsequent holder of Company Securities subject to this Agreement at such
address as indicated by the Company's records, or at such address or to the
attention of such other Person as the recipient party has specified by prior
written notice to the sending party. Notices shall be deemed to have been given
hereunder (a) upon receipt by or delivery to the recipient party, (b) upon
personal delivery as set forth above, or (c) the date delivery is confirmed by
facsimile or reputable overnight courier as set forth above; provided that any
service of process or other notice of any court or other legal proceeding or
action shall be made by personal delivery to the recipient or its agent for
service of process (including the Process Agent (as defined below) and any of
its employees). Each notice delivered under this Agreement shall be made in
English and the English version shall govern in the event of any inconsistency
with any non-English translation thereof.

          (b) The delivery to the Common Representative of any notice required
to be given under this Agreement is in addition to (and not in lieu of) any
obligation to deliver notice under this Agreement to a CPO Holder.

          19. Governing Law; Jurisdiction. UNLESS AND EXCEPT TO THE EXTENT ANY
PROVISION HEREOF IS REQUIRED BY MEXICAN LAW TO BE GOVERNED BY MEXICAN LAW, THIS
AGREEMENT, ITS INTERPRETATION AND ENFORCEABILITY AND THE RIGHTS AND OBLIGATIONS
OF THE PARTIES HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND BE GOVERNED
BY THE INTERNAL LAWS (AND NOT THE LAWS OF CONFLICT) OF THE STATE OF ILLINOIS,
UNITED STATES OF AMERICA. Any legal action or proceeding to enforce the
obligation of any party to resolve any dispute in accordance with Section 20 or
to enforce an order or award made pursuant to an arbitration under Section 20
may be brought in (a) the courts of the State of Illinois, United States of
America, (b) the courts of the United States for the Northern District of
Illinois, or (c) the competent courts of Mexico, D.F., pursuant to the New York
Convention for the Recognition and Enforcement of Foreign Arbitration Awards, or
(iv) any other court of competent jurisdiction and, by execution and delivery of
this Agreement, each party hereby irrevocably accepts for itself and in respect
of its property, generally and unconditionally, the jurisdiction of each of the
aforesaid courts. The Company, each Existing Securityholder and each Other
Securityholder not resident in or organized under the laws of the United States
each hereby irrevocably appoints CT Corporation (the "Process Agent") (a process
agent service company located in the United States at 208 S. LaSalle Street,
Chicago, Illinois, 60604), as its authorized agent for service of process in any
such court and notice under this Agreement and agrees to maintain such
appointment for so long as any Investor owns any Securities and to further
evidence such appointment in an escritura publica executed before a notary
public in Mexico in conformity with Article 2596 of the Civil Code of the
Federal District and the 1958 Protocol on the Uniformity of Powers of Attorney
to be Utilized Abroad. The Company shall pay all expenses in connection with
such appointment of CT Corporation as the Company's and such Existing
Securityholders' and Other Securityholders' agent. Each party hereby further
irrevocably waives any claim





                                     E-150
<PAGE>   30

that any such courts lack jurisdiction over such party or that service of
process or venue is improper, and agrees not to plead or claim, in any legal
action or proceeding with respect to this Agreement brought in any of the
aforesaid courts, that any such court lacks jurisdiction over such party or that
venue or service of process is improper or that the action has been brought in
an inconvenient forum. Nothing herein shall affect the right of any Investor to
serve process in any other manner permitted by law.

          20. Arbitration. If any dispute or claim arises out of this Agreement,
or as to the rights and liabilities of the parties hereunder, or as to the
breach or invalidity hereof, or in connection with the construction of this
Agreement, including any dispute, claim or difference as to whether an issue is
arbitrable, the parties shall settle such dispute exclusively by binding
arbitration by an arbitrator appointed by the International Chamber of Commerce
in accordance with the rules of the International Chamber of Commerce in New
York City in effect as of the date of commencement of the arbitration. The
arbitration shall be commenced by the delivery of written notice by the party
seeking arbitration to the other parties to the dispute, shall be held in New
York City, New York, unless the parties mutually agree to have the arbitration
held elsewhere, shall be conducted solely in the English language, shall utilize
the English versions of all of the Transaction Agreements and the Company's
By-laws and judgment upon the award made therein may be entered by any court
having jurisdiction thereover; provided that nothing contained in this Section
20 shall be construed to limit or preclude a party from bringing any action in
any court of competent jurisdiction in the United States or Mexico solely for
the purpose of enforcing any final judgment or award made pursuant to an
arbitration under this Section 20 or enforcing the obligation of any other party
hereto to resolve any dispute in accordance with this Section 20.
Notwithstanding anything to the contrary in this Agreement, the unsuccessful
party in any such arbitration proceeding shall pay to the successful parties all
costs and expenses incurred by the successful party in connection with such
arbitration proceeding, including all costs and expenses of outside counsel and
all reasonable costs and expenses of their advisers.

          21. Governing Language. This Agreement has been negotiated and
executed by the parties hereto in English. A Spanish translation of this
Agreement has been prepared solely for convenience. As among the Company and the
Securityholders, in the event of any inconsistency between or among the
non-English and the English versions of this Agreement, the Neutral Investment
Trust Agreement, the Security Trust Agreement and any other Transaction
Agreement or the Company's By-laws, the provisions of the English version shall
prevail.

          22. Rule of Construction. Each of the parties hereto acknowledge and
agree that such party and its counsel have reviewed and revised this Agreement
and that the normal rule of construction to the effect that any ambiguities are
to be resolved against the drafting party shall not be employed in the
interpretation of this Agreement or any amendment, exhibit or schedule hereto.

          23. Complete Agreement. This Agreement, the Neutral Investment Trust
Agreement, the Security Trust Agreement, the other Transaction Agreements and
the other documents and writings expressly referred to herein or therein or
delivered pursuant hereto or thereto (in their English versions) contain the
entire understanding of the parties hereto with respect to the subject matter
hereof and thereof and supersede all prior agreements, representations and
understandings, whether written and oral, among any of the parties with respect
to the subject matter hereof and thereof (including without limitation, the
Original Shareholders Agreement).

          24. Special Provisions for Option Holders.

          Pursuant to the Restructuring, fifty percent (50%) of the Series N
Shares held by the Company as treasury shares and reserved for issuance pursuant
to the terms of the Company's stock options were converted into Series C Shares
and will be deposited into the Neutral Investment Trust, along with a
corresponding number of Series N Shares (held by the Company as treasury shares
and reserved for issuance pursuant to the terms of the Company's stock options)
upon the proper exercise of such options (including the payment by the option
holder to the Company of the consideration for such Company Shares) pursuant to
the terms of the Company's stock options. Upon (i) the Company's receipt of the
requisite consideration upon the exercise of a Company stock option for the
acquisition of Series N Shares, (ii) the optionee's compliance with the terms of
this Agreement, including the execution of such optionee of a counterpart
signature page to this Agreement which binds it to the provisions of this
Agreement, and (iii) the optionee's compliance with the terms of Neutral
Investment Trust Agreement relating to the admission of new settlors thereunder,
the Company will cause the NIT Trustee to issue CPOs to such optionee in





                                     E-151
<PAGE>   31

lieu of Series N Shares (with the number of CPOs being issued thereunder equal
to one CPO for each two Series N Shares previously issuable pursuant to such
stock option).

          (a) B&A Options. The option (the "B&A Option") for the acquisition of
Series N Shares (shares acquired pursuant to the B&A Option or as a result of a
non-prohibited assignment or transfer thereof being referred to herein as "B&A
Shares") granted to Bachow & Associates, Inc. (together with any other holder of
the B&A Option, "B&A") pursuant to the Strategic Assistance Agreement has been
exercised prior to the date hereof and the consideration for such B&A Shares
delivered by B&A, however the B&A Shares have not yet been issued to B&A by the
Company. Subject to the execution by B&A of a counterpart signature page to this
Agreement which binds it to the provisions of this Agreement, including the
substitution of the CPOs for the B&A Shares, the parties hereto hereby agree
that CPOs may be issued to B&A in lieu of the B&A Shares, subject to the terms
of the B&A Option and the Strategic Assistance Agreement, without any further
action or approval by any of Securityholders or the Board and that B&A, upon its
receipt of such CPOs, shall for all purposes of this Agreement be deemed to be
an "Investor," a "CPO Holder" and a "Securityholder."

          (b) CTGT Options. The Operating Agreement grants options ("CTGT
Options") to CTGT (together with any other holder of any CTGT Options, "CT") for
the acquisition of Series N Shares (shares acquired pursuant to the CTGT Options
or as a result of a non-prohibited assignment or transfer thereof being referred
to herein as "CTGT Shares") as set forth therein. Subject to the execution by CT
of a counterpart signature page to this Agreement which binds it to the
provisions of this Agreement, including the substitution of the CPOs for the
CTGT Shares, the parties hereto hereby agree that the CTGT Options may be
exercised from time to time and the CPOs may be issued upon each such exercise
in lieu of the CTGT Shares, in each case subject to the terms of the Operating
Agreement, without any further action or approval by any of the Securityholders
or the Board and that CT, upon the exercise of any CTGT Options, shall for all
purposes of this Agreement be deemed to be an "Existing Securityholder," a "CPO
Holder" and a "Securityholder."

          (c) Management Options. The Management Option Plan (as defined in the
Subscription Agreement) grants options ("Management Options") to members of the
Company's management for the acquisition of Series N Shares (shares acquired
pursuant to the Management Options or as a result of a non-prohibited assignment
or transfer thereof being referred to herein as "Management Shares") as set
forth therein. Subject to the execution by each recipient of a Management Option
of a counterpart signature page to this Agreement which binds it to the
provisions of this Agreement, including the substitution of the CPOs for the
Management Shares, the parties hereto hereby agree that the Management Options
may be exercised from time to time and the CPOs may be issued upon each such
exercise in lieu of the Management Shares, in each case subject to the terms of
the Management Option Plan, without any further action or approval by any of the
Securityholders or the Board and that each recipient of a Management Option,
upon the exercise of any such Management Option, shall for all purposes of this
Agreement be deemed to be an "Existing Securityholder," a "CPO Holder" and a
"Securityholder."

          (d) Amsterdam Options. The Engagement Letter grants options
("Amsterdam Options") to Amsterdam Pacific LLC (together with any other holder
of any Amsterdam Options, "APLLC") for the acquisition of Series N Shares
(shares acquired pursuant to the Amsterdam Options or as a result of a
non-prohibited assignment or transfer thereof being referred to herein as
"Amsterdam Shares") as set forth therein. Subject to the execution by APLLC of a
counterpart signature page to this Agreement which binds it to the provisions of
this Agreement, including the substitution of the CPOs for the Amsterdam Shares,
the parties hereto hereby agree that the Amsterdam Options may be exercised from
time to time and the CPOs may be issued upon each such exercise in lieu of the
Amsterdam Shares, in each case subject to the terms of the Engagement Letter,
without any further action or approval by any of the Securityholders or the
Board and that APLLC, upon the exercise of any Amsterdam Options, shall for all
purposes of this Agreement be deemed to be an "Other Securityholder," a "CPO
Holder" and a "Securityholder."

          25. Termination of Agreement. Notwithstanding anything to the contrary
contained in this Agreement, at such time as (i) the rights of all Investors to
designate any members of the Board pursuant to Section 1 have terminated, then
Sections 6(c), 6(d) and 6(e) shall automatically terminate and be of no further
force or effect and (ii) the Investors collectively hold, directly or
indirectly, less than ten percent (10%) of the outstanding Company Shares
(including, for purposes of such calculation, the indirect ownership of the
shares represented by the





                                     E-152
<PAGE>   32

CPOs (i.e., each CPO shall count as one Series C Share and one Series N Share),
this Agreement shall automatically terminate and be of no further force or
effect.

          26. Third Party Beneficiary. Notwithstanding anything to the contrary
contained in this Agreement (as it may be amended from time to time in
accordance with its terms), each of the parties hereto acknowledge and agree
that the NIT Trustee shall be and is a third party beneficiary of this
Agreement, and as such, so long as the Neutral Investment Trust's trust estate
includes Series C Shares or Series N Shares, the NIT Trustee and its duly
authorized designees are each entitled to enforce all of the rights in this
Agreement relating to the Series C Shares and Series N Shares as if the NIT
Trustee were a party to this Agreement.

          27. Understanding Among the Securityholders. The determination of each
Securityholder to acquire Company Securities and enter into this Agreement has
been made by such Securityholder independent of any other Securityholder and
independent of any statements or opinions as to the advisability of such
purchase or as to the properties, business, prospects or condition (financial or
otherwise) of the Company and its subsidiaries which may have been made or given
to such Securityholder by any other Securityholder or by any agent or employee
of any other Securityholder. Each Securityholder acknowledges and agrees that no
other Securityholder shall be responsible in any way or held liable or
accountable to any extent for any information, documents, materials, analysis,
projections, plans or other data (or compilations thereof) relating to the
Company or the transactions contemplated hereby (collectively, "Investment
Data") provided to such Securityholder by any other Securityholder, and each
Securityholder agrees to hold harmless and not make any claims against any other
Securityholder with respect to any Investment Data provided to such
Securityholder by such other Securityholder. In addition, it is acknowledged by
each of the other Securityholders that none of BankAmerica International
Investment Corporation, LA Strategic Partners II, BancBoston Investments, Inc.
or Bachow Investment Partners III, L.P. has acted as an agent of such
Securityholder in connection with the making of its investment in the Company
Securities and that none of Bankamerica International Investment Corporation, LA
Strategic Partners II, BancBoston Investments, Inc. or Bachow Investment
Partners III, L.P. is or shall be acting as an agent of such Securityholder in
connection with monitoring its investment hereunder.

          28. Acknowledgment re Kirkland & Ellis. Bankamerica International
Investment Corporation, LA Strategic Partners II, BancBoston Investments, Inc.
and Bachow Investment Partners III, L.P. have retained Kirkland & Ellis in
connection with this Agreement and may in the future retain Kirkland & Ellis in
connection with the matters contemplated by this Agreement. Each of the other
Securityholders understands that Kirkland & Ellis is not representing and shall
not be deemed to be representing any of such other Securityholder in connection
with this Agreement or other matters contemplated by this Agreement unless and
until (i) specifically requested by such other Securityholder and agreed to by
Kirkland & Ellis, and (ii) such other Securityholder signs a written retention
and conflict waiver letter provided by Kirkland & Ellis.




                                     E-153