EXHIBIT 10.1

                          THIRD AMENDED AND RESTATED

                            STOCKHOLDERS AGREEMENT


                                     among


                               IFX CORPORATION,

                        UBS CAPITAL AMERICAS III, L.P.,

                               UBS CAPITAL LLC,

                   INTERNATIONAL TECHNOLOGY INVESTMENTS, LC,

                               JOEL EIDELSTEIN,

                                MICHAEL SHALOM,

                                      and

                                 LEE S. CASTY



                         dated as of February 19, 2002


                                IFX CORPORATION


               THIRD AMENDED AND RESTATED STOCKHOLDERS AGREEMENT


     THIS THIRD AMENDED AND RESTATED STOCKHOLDERS AGREEMENT (this "Agreement")
is entered as of February 19, 2002, among IFX CORPORATION, a Delaware
corporation (the "Company"), UBS CAPITAL AMERICAS III, L.P., a Jersey, Channel
Islands limited partnership, and UBS CAPITAL LLC, a Delaware limited liability
company (collectively, "UBS" and together with successors and assigns, the
"Investor Stockholders"), INTERNATIONAL TECHNOLOGY INVESTMENTS, LC, a Nevada
limited liability company ("ITI"), JOEL EIDELSTEIN, individually ("Eidelstein"),
MICHEAL SHALOM, individually ("Shalom"), and LEE S. CASTY, successor in interest
to Casty Grantor Subtrust ("Casty"; ITI, Shalom, Eidelstein, Casty and any other
Person who becomes a party to this Agreement pursuant to the last sentence of
Section 5.2, individually, a "Stockholder," and collectively, the
"Stockholders").

                                    RECITALS
                                    --------

     WHEREAS, the Company and the Investor Stockholders entered into that
certain IFX Corporation Preferred Stock Purchase Agreement, dated as of June 15,
2000, pursuant to which the Investor Stockholders purchased 2,030,869 shares of
Series A Preferred Stock; and

     WHEREAS, as a condition to and in consideration of the Investor
Stockholders' purchase of Series A Preferred Stock, the Company, the Investor
Stockholders and the Stockholders entered into that certain Amended and Restated
Stockholders Agreement dated as of June 15, 2000; and

     WHEREAS, the Company and the Investor Stockholders entered into that
certain IFX Corporation Preferred Stock Purchase Agreement, dated March 13,
2001, pursuant to which the Investor Stockholders purchased 4,418,262 shares of
Series B Preferred Stock; and

     WHEREAS, as a condition to and in consideration of the Investor
Stockholders' purchase of Series B Preferred Stock, the Company, the Investor
Stockholders, Casty Grantor Subtrust and the Stockholders (except Casty) entered
into that certain Second Amended and Restated Stockholders Agreement dated as of
May 7, 2001 (the "Existing Agreement"); and

     WHEREAS, the Company and the Investor Stockholders have entered into the
IFX Corporation Series C Convertible Preferred Stock Purchase Agreement, dated
October 11, 2001 (the "Stock Purchase Agreement"), pursuant to which the
Investor Stockholders will acquire shares of newly issued Series C Preferred
Stock; and

     WHEREAS, as a condition to and in consideration of the Investor
Stockholders' purchase of Series C Preferred Stock, the Company, the Investor
Stockholders and the

                                       1


Stockholders have agreed to amend and restate the Existing Agreement in the
manner set forth below.

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained in this Agreement and for other valuable consideration the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

                                   ARTICLE I

                                  DEFINITIONS

     SECTION 1.1   Certain Defined Terms.  As used herein, the following terms
                   ---------------------
shall have the following meanings:

     "Affiliate" of a specified Person shall mean (a) any Person that directly
or indirectly, through one or more intermediaries, controls, is controlled by,
or is under common control with, such specified Person, (b) in the case of a
natural Person, such Person's spouse, parent or lineal descendant (whether by
blood or adoption and including stepchildren), a trust primarily for the benefit
of such Person and the foregoing, (c) in the case of a trust any Person with
whom the beneficiaries of the Trust are Affiliates, or (d) in the case of UBS,
(i) any company under the direct or indirect control of UBS AG (a "UBS Group
Company") and/or any partnership or unincorporated association under the direct
or indirect control of any UBS Group Company which includes, without limiting
the generality of the foregoing, any limited partnership the general partner of
which is a UBS Group Company and any limited liability company the managing
member of which is a UBS Group Company, and (ii) any alternative investment
vehicle formed by either of the foregoing, or any other entity (x) in which UBS
AG directly or indirectly owns at least 20% of the equity interests and (y) is
advised or managed (whether pursuant to contract, as general partner, managing
member or otherwise) by an entity in which UBS AG has a direct or indirect
equity interest.

     "Agent" has the meaning assigned to such term in Section 5.13.

     "as converted" has the meaning assigned to such term in Section 2.3.

     "beneficial owner" or "beneficially own" has the meaning given such term in
Rule 13d-3 under the Exchange Act and a Person's beneficial ownership of Common
Stock, Preferred Stock or other Voting Securities of the Company shall be
calculated in accordance with the provisions of such Rule; provided, however,
that for purposes of determining beneficial ownership, (i) a Person shall be
deemed to be the beneficial owner of any security which may be acquired by such
Person whether within 60 days or thereafter, upon the conversion, exchange or
exercise of any warrants, options, rights or other securities and (ii) no Person
shall be deemed to beneficially own any security solely as a result of such
Person's execution of this Agreement.

     "Board" means the Board of Directors of the Company.

                                       2


     "Bona Fide Purchaser" means, with respect to a proposed Transfer of Equity
Securities, any transferee of Equity Securities who or which (a) is not an
Affiliate of the Investor Stockholders and (b) has delivered a good faith
written offer to purchase Equity Securities.

     "Business Day" means any day that is not a Saturday, a Sunday or other day
on which banks are required or authorized by law to be closed in New York City
on the city of Miami, Florida.

     "Buyer" has the meaning assigned to such term in Section 3.6.

     "Bylaws" means the Bylaws of the Company, as in effect on the date hereof
and as the same may be amended, supplemented or otherwise modified from time to
time in accordance with the terms thereof, the terms of the Certificate and the
terms of this Agreement.

     "Capital Stock" means, with respect to any Person at any time, any and all
shares, interests, participations or other equivalents (however designated,
whether voting or non-voting) of capital stock, partnership interests (whether
general or limited) or equivalent ownership interests in or issued by such
Person, and includes, in the case of the Company without limitation, any and all
shares of Common Stock and Preferred Stock.

     "Casty" has the meaning assigned to such term in the preamble.

     "Certificate" means the Certificate of Incorporation of the Company, as in
effect on the date hereof and as the same may be amended, supplemented or
otherwise modified from time to time in accordance with the terms thereof.

     "Certificates of Designation" means, collectively, the Series A Certificate
of Designation, the Series B Certificate of Designation and the Series C
Certificate of Designation.

     "Closing" has the meaning assigned to such term in the Stock Purchase
Agreement.

     "Common Stock" means the common stock, par value $0.02 per share, of the
Company and any securities issued in respect thereof, or in substitution
therefor, in connection with any stock split, dividend or combination, or any
reclassification, recapitalization, merger, consolidation, exchange or other
similar reorganization.

     "control" (including the terms "controlled by" and "under common control
with"), with respect to the relationship between or among two or more Persons,
means the possession, directly or indirectly, of the power to direct or cause
the direction of the affairs or management of a Person, whether through the
ownership of voting securities, as trustee or executor, by contract or
otherwise.

     "Director" means any member of the Board.

     "Eidelstein" has the meaning assigned to such term in the preamble.

                                       3


     "Equity Securities" means any and all shares of Capital Stock of the
Company, securities of the Company convertible into, or exchangeable or
exercisable for, such shares, and options, warrants or other rights to acquire
such shares.

     "Exchange Act" means the Securities Exchange Act of 1934, as amended, or
any similar federal statute and the rules and regulations promulgated
thereunder.

     "Family" means any spouse, lineal ancestor or descendant, brother or sister

     "Holder" means an Investor Stockholder and any other holder of Equity
Securities who or which is a permitted transferee of an Investor Stockholders
pursuant to Section 3.1(c).

     "Independent Director" has the meaning specified in Rule 4200(a)(14) of the
NASD listing standards, as in effect on the date hereof and as the same may be
amended or supplemented, or in any successor rule or regulation.

     "Independent Representative" has the meaning assigned to such term in
Section 2.1(a).

     "Investor Representative" has the meaning assigned to such term in Section
2.1(a).

     "ITI" has the meaning assigned to such term in the preamble.

     "NASD" means the National Association of Securities Dealers, Inc.

     "Offer" has the meaning assigned to such term in Section 3.5(a).

     "Offered Shares" has the meaning assigned to such term in Section 3.5(a).

     "Permitted Sales" means (i) in the case of ITI and Shalom the Transfers
permitted in the first sentence of Section 3.3(a), (ii) in the case of
Eidelstein, the Transfers permitted in the second sentence of Section 3.3(a),
(iii) in the case of Casty, the Transfers permitted in the first sentence of
Section 3.4(a) and (iv) in the case of any other Stockholder, Transfers to or
among such Stockholder's Affiliates.

     "Person" means any individual, corporation, limited liability company,
limited or general partnership, joint venture, association, joint-stock company,
trust, unincorporated organization, government or any agency or political
subdivisions thereof or any other entity.

     "Preferred Stock" means the Series A Preferred Stock, Series B Preferred
Stock, Series C Preferred Stock and any other class or series of preferred stock
of the Company which is convertible, directly or indirectly, into Common Stock,
whether at the time of issuance or upon passage of time or the occurrence of
some future event.

     "Proposed Transferee" has the meaning assigned to such term in Section
3.5(a).

     "Pro Rata Fraction" has the meaning assigned to such term in Section
3.5(c).

                                       4


     "Qualified Public Offering" has the meaning assigned to such term in the
Stock Purchase Agreement.

     "Registration Rights Agreement" has the meaning assigned to such term in
the Stock Purchase Agreement.

     "Representatives" has the meaning assigned to such term in Section 2.1(b).

     "SEC" means the U.S. Securities and Exchange Commission or any other
federal agency then administering the federal securities laws.

     "Securities Act" has the meaning assigned to such term in Section 3.1.

     "Seller" has the meaning assigned to such term in Section 3.5(a).

     "Series A Certificate of Designation" means the Amended Certificate of
Designation, Number, Powers, Preferences and Relative, Participating and Other
Rights of Series A Convertible Preferred Stock of the Company in the form filed
with the Secretary of State of the State of Delaware, as amended from time to
time.

     "Series B Certificate of Designation" means the Amended Certificate of
Designation, Number, Powers, Preferences and Relative, Participating and Other
Rights of Series B Convertible Preferred Stock of the Company in the form filed
with the Secretary of State of the State of Delaware, as amended from time to
time.

     "Series C Certificate of Designation" means the Certificate of Designation,
Number, Powers, Preferences and Relative, Participating and Other Rights of
Series C Convertible Preferred Stock of the Company in the form filed with the
Secretary of State of the State of Delaware, as amended from time to time.

     "Series A Preferred Stock" means the Series A Convertible Preferred Stock,
par value $1.00 per share, of the Company.

     "Series B Preferred Stock" means the Series B Convertible Preferred Stock,
par value $1.00 per share, of the Company.

     "Series C Preferred Stock" means the Series C Convertible Preferred Stock,
par value $1.00 per share, of the Company.

     "Shalom" has the meaning assigned to such term in the preamble.

     "Stockholders" has the meaning assigned to such term in the preamble.

     "Stock Purchase Agreement" has the meaning assigned to such term in the
recitals.

     "Transfer" means, directly or indirectly, to sell, transfer, assign,
pledge, encumber, hypothecate or similarly dispose of, either voluntarily or
involuntarily, or to enter into any contract, option or other arrangement or
understanding with respect to the sale, transfer, assignment, pledge,
encumbrance, hypothecation or similar disposition of,

                                       5


any shares of Equity Securities beneficially owned by a Person or any interest
in any shares of Equity Securities beneficially owned by a Person.

     "UBS" means (i) UBS Capital Americas III, L.P., a Jersey, Channel Islands
limited partnership, (ii) UBS Capital LLC, a Delaware limited liability Company,
and (iii) any Affiliate of UBS, individually and collectively.

     "Voting Securities" means, at any time, shares of any class of Equity
Securities of the Company which are then entitled to vote generally in the
election of Directors.

     SECTION 1.2    Other Definitional Provisions.
                    -----------------------------

          (a)  The words "hereof", "herein" and "hereunder" and words of similar
  import when used in this Agreement shall refer to this Agreement as a whole
  and not to any particular provision of this Agreement, and Article and Section
  references are to this Agreement unless otherwise specified.

          (b)  The meanings given to terms defined herein shall be equally
  applicable to both the singular and plural forms of such terms.


                                  ARTICLE II

                             CORPORATE GOVERNANCE

     SECTION 2.1    Board Representation.
                    --------------------

          (a)  Effective on the date hereof, the Board shall be comprised of
  seven (7) Directors of whom: (i) three (3) shall be designees of the Investor
  Stockholders (the "Investor Representatives"), (ii) one (1) shall be the
  designee of ITI (the "ITI Representative"), (iii) one (1) shall be the
  designee of Casty (the "Casty Representative"), (iv) one (1) shall be an
  Independent Director designated by the Investor Stockholders (the "Investor
  Independent Representative") and (v) one (1) shall be an Independent Director
  acceptable to the Investor Stockholders, Casty and ITI (with such consents not
  to be unreasonably withheld or delayed) (the "Independent Representative").
  The initial Investor Representatives shall be Charles W. Moore, Mark O. Lama
  and Charles Delaney, the initial ITI Representative shall be Shalom, the
  initial Casty Representative shall be Eidelstein, the initial Investor
  Independent Representative shall be Patrick Delhougne and the initial
  Independent Representative shall be Burton Meyer. For purposes hereof, each of
  the three Investor Representatives and the Investor Independent Representative
  shall count as one of the four Preferred Directors (as defined in the
  Certificates of Designation).

          (b)  The Company shall take such action as may be required under
  applicable law (i) to cause the Board to consist of the number of Directors
  specified in clause (a), (ii) to include in the slate of nominees recommended
  by the Board the Investor Representatives, the ITI Representative, the Casty
  Representative, the Investor Independent Representative and the Independent
  Representative

                                       6


  (collectively, the "Representatives"), and (iii) to cause the Representatives
  to be duly appointed in accordance with the foregoing and, in the case of the
  Investor Representatives, in accordance with the Certificates of Designation.
  The Company agrees to use its reasonable best efforts to cause the election of
  the Representatives to the Board, including nominating such individuals to be
  elected as Directors as provided herein.

          (c)  Each of the Investor Stockholders and the Stockholders agrees to
  vote, or act by written consent with respect to any Voting Securities
  beneficially owned by him or it, at each annual or special meeting of the
  stockholders of the Company at which Directors are to be elected or to take
  all actions by written consent in lieu of any such meeting as are necessary to
  cause the Representatives designated by the others in accordance with the
  terms of this Agreement to be elected to the Board and agrees to use his or
  its reasonable best efforts to cause the election of each such designee to the
  Board, including nominating such individuals to be elected as Directors.

          (d)  In the event that a vacancy is created at any time by the death,
  disability, retirement, resignation or removal (with or without cause) of any
  Representative, the remaining Directors and the Company shall cause the
  vacancy created thereby to be filled by a new designee of the party or parties
  that designated such Director as soon as possible, who is designated in the
  manner specified in this Section 2.1. Each of the Company, Investor
  Stockholders and the Stockholders hereby agrees to take, at any time and from
  time to time, all actions necessary to accomplish the same. Upon the written
  request of any party who is entitled to designate a Representative, each of
  the Investor Stockholders and Stockholders shall vote, or act by written
  consent with respect to all Voting Securities beneficially owned by him or it
  and otherwise take or cause to be taken all actions necessary to remove any
  Director designated by such party. Unless, any party who is entitled to
  designated a Representative shall otherwise request in writing, none of the
  others shall take any action to cause the removal of any Director designated
  by the former.

          (e)  Each of the Company, the Investor Stockholders and the
  Stockholders agrees not to take any action that would cause the number of
  Directors constituting the entire Board to be other than the number provided
  in Section 2.1(a) without the written consent of each other party entitled to
  designate a Representative.

          (f)  The covenants and agreements set forth herein shall be subject to
  the fiduciary obligations of the Representatives now or hereafter serving on
  the Board and shall not prevent the Representatives now or hereafter serving
  on the Board from taking any action or refraining to take any action while
  acting in the capacity as a Director of the Company. The foregoing shall not
  limit the rights or obligations of the Investor Stockholders, ITI and Casty in
  their capacity as stockholders of the Company hereunder.

     SECTION 2.2    Committees.  The Company shall, except as provided below, by
                    ----------
amending its Bylaws or otherwise, establish and maintain a Compensation
Committee and an Audit Committee of the Board which satisfies the requirements
of this Section. The Compensation Committee shall consist of three (3)
Directors, one (1) of whom shall

                                       7


be an Investor Representative and two (2) of whom shall be Independent
Representatives. The Audit Committee shall consist of three (3) Directors, one
(1) of whom shall be an Investor Representative and two (2) of whom shall be
Independent Representatives. The Compensation Committee shall have
responsibility for compensation matters customarily addressed by compensation
committees of similarly situated companies and shall have the full power and
authority of the Board with respect thereto, except as limited by applicable
law. The Audit Committee shall have responsibility for matters customarily
addressed by audit committees of similarly situated companies and shall have the
full power and authority of the Board with respect thereto, except as limited by
applicable law. Notwithstanding anything to the contrary herein, the Investor
Stockholders and the Stockholders acknowledge and agree that the composition of
the Compensation and Audit Committees must satisfy any applicable rules and
regulations of the SEC and the NASD as in effect from time to time.

     SECTION 2.3    Termination of Rights.
                    ---------------------

          (a)  Except with respect to the rights of the Investor Stockholders as
  provided in subparagraph (b) below, Sections 2.1 and 2.2 shall terminate upon
  a Qualified Public Offering. Prior to a Qualified Public Offering, the rights
  of the Investor Stockholders and any Stockholder under Sections 2.1 and 2.2
  (and the corresponding obligation of the Stockholders) shall terminate at such
  time as such Investor Stockholder or Stockholders, as the case may be, ceases
  to own at least 25% of the number of shares of Common Stock on an as converted
  basis that such Investor Stockholder or Stockholders held as of Closing.

          (b)  The rights of the Investor Stockholders under Sections 2.1 and
  2.2 (and the corresponding obligations of the Stockholders) shall survive a
  Qualified Public Offering, provided that, at such time as the Investor
  Stockholders and their Affiliates shall cease to own in the aggregate at least
  25% of the number of shares of Common Stock (determined with respect to the
  Preferred Stock and any other Equity Securities owned by the Investor
  Stockholders and their Affiliates that are convertible into (whether or not,
  in the case of the Preferred Stock, such Preferred Stock is then currently
  convertible at the option of the holder into Common Stock), or exchangeable or
  exercisable for Common Stock, on an as-converted, exchanged or exercised basis
  (any determination made in accordance with the foregoing shall hereinafter be
  referred to as "as converted")) that the Investor Stockholders and such
  Affiliates held as of the Closing (adjusted for stock splits, combinations,
  stock dividends and the like), the Investor Stockholders shall cease to have
  the right to designate Directors pursuant to Section 2.1 and members of the
  Compensation Committee and Audit Committee pursuant to Section 2.2 and all
  other rights of the Investor Stockholders under this Article II shall
  terminate.


                                  ARTICLE III

                                   TRANSFERS

     SECTION 3.1    Investor Stockholder Transfers.  Each Investor Stockholder
                    ------------------------------
hereby agrees that it shall not Transfer any shares of its Equity Securities,
unless such

                                       8


Transfer is effected through (a) a public offering registered under
the Securities Act of 1933, as amended, and the rules and regulations
promulgated thereunder (the "Securities Act"), (b) sales made pursuant to Rule
144 under the Securities Act, or any successor provisions or (c) a Transfer
otherwise permitted hereunder and in compliance herewith. Any Equity Securities
Transferred pursuant to clause (a) or (b) shall no longer be subject to this
Agreement. Each transferee Holder under clause (c) shall agree in writing as a
condition to such Transfer, to be bound by all of the provisions of this
Agreement to the same extent as if such transferee were the transferring
Investor Stockholder, and all stock certificates representing shares transferred
to such transferee shall bear a legend providing notice of the restrictions
contained in this Agreement.

     SECTION 3.2    Stockholder Transfers.  Each Stockholder hereby agrees that
                    ---------------------
it shall not Transfer any shares of its Equity Securities, unless such Transfer
is effected through (a) a public offering registered under the Securities Act,
(b) sales made pursuant to Rule 144 under the Securities Act or any successor
provisions or (c) a Transfer otherwise permitted hereunder and in compliance
herewith. Any Equity Securities Transferred pursuant to clauses (a) or (b) shall
no longer be subject to this Agreement, except as provided herein. Each
transferee under clause (c) shall agree in writing as a condition to such
Transfer, to be bound by all of the provisions of this Agreement to the same
extent as if such transferee were the transferring Stockholder, and all stock
certificates representing shares transferred to such transferee shall bear a
legend providing notice of the restrictions contained in this Agreement.

     SECTION 3.3    Transfers by Eidelstein, ITI and Shalom.
                    ---------------------------------------

          (a)  ITI and Shalom agree that neither such Stockholder nor any of its
  Affiliates shall Transfer more than 25,000 shares of Common Stock during any
  calendar quarter, in each case, without the written consent of the Investor
  Stockholders, which consent shall not be unreasonably withheld or delayed, or
  without compliance with Sections 3.5 and 3.6; provided that Transfers by ITI
  and Shalom shall be aggregated for purposes of the foregoing. Eidelstein
  hereby agrees that neither he nor any of his Affiliates shall Transfer more
  than 25,000 shares of Common Stock during any calendar quarter without the
  written consent of the Investor Stockholders, which consent shall not be
  unreasonably withheld or delayed, or without compliance with Sections 3.5 and
  3.6. Notwithstanding the foregoing, Eidelstein, ITI or Shalom may Transfer all
  or any of their Equity Securities (x) to any member of such Stockholder's
  Family or to any trust for the benefit of any such Family member of such
  Stockholder or to any other Affiliate (including, without limitation, the
  members of ITI), provided that any such transferee shall agree in writing with
  the Company and the Investor Stockholders as a condition to such Transfer, to
  be bound by all of the provisions of this Agreement to the same extent as if
  such transferee were such Stockholder, or (y) by will or the laws of descent
  and distribution; provided, however, in such event each such transferee shall
  be bound by all of the provisions of this Agreement to the same extent as if
  such transferee were such Stockholder; and provided, further, that each such
  transferee shall execute an irrevocable proxy appointing _____________________
  as proxy to vote all such shares so transferred, such appointment shall be
  coupled with an interest, and all

                                       9


  stock certificates representing such shares shall bear a legend providing
  notice of such appointment of proxy and the restrictions contained in this
  Agreement.

          (b)  The Transfer restrictions contained in Section 3.3(a) shall
  terminate upon the earlier of: (i) a Qualified Public Offering and (ii) the
  time at which the Investor Stockholders and the other Holders own less than
  20% of the Common Stock (on an as converted basis) that the Investor
  Stockholders owned as of the Closing.

     SECTION 3.4    Transfers by Casty.
                    ------------------

          (a)  Casty agrees that neither it nor any of its Affiliates shall
  Transfer, during any calendar quarter, more than the number of Shares of
  Common Stock permitted under Rule 144(e) of the Securities Act measured as of
  the last day of such calendar quarter plus 50% of the number of Shares of
  Common Stock which were eligible for sale (but not sold under this Section
  3.4(a)) during the preceding calendar quarters (beginning with the calendar
  quarter ending March 31, 2001), without the written consent of the Investor
  Stockholders, which consent shall not be unreasonably withheld or delayed, or
  without compliance with Sections 3.5 and 3.6. Notwithstanding the foregoing,
  Casty may Transfer all or any of his Equity Securities (x) to any member of
  such Stockholder's Family, to any trust for the benefit of any such Family
  member of such Stockholder or to any other Affiliate, provided that any such
  transferee shall agree in writing as a condition to such Transfer, to be bound
  by all of the provisions of this Agreement to the same extent as if such
  transferee were such Stockholder, or (y) by will or the laws of descent and
  distribution; provided, however, in such event each such transferee shall be
  bound by all of the provisions of this Agreement to the same extent as if such
  transferee were such Stockholder; and provided, further, that each such
  transferee shall execute an irrevocable proxy appointing Joel Eidelstein as
  proxy to vote all such shares so transferred, such appointment shall be
  coupled with an interest, and all stock certificates representing such shares
  shall bear a legend providing notice of such appointment of proxy and the
  restrictions contained in this Agreement.

          (b)  The Transfer restrictions contained in Section 3.4(a) shall
  terminate upon the earlier of: (i) a Qualified Public Offering and (ii) the
  time at which the Investor Stockholders and the other Holders own less than
  20% of the Common Stock (on an as converted basis) that the Investor
  Stockholders owned as of the Closing.

     SECTION 3.5    Right of First Refusal on Certain Transfers.
                    -------------------------------------------

          (a)  If at any time a Stockholder or any of his/its Affiliates, other
than the Company, desires to Transfer all or any part of their Equity Securities
(other than pursuant to Permitted Sales) to any Person (the "Proposed
Transferee"), such Stockholder (the "Seller") shall, except as provided below,
submit a written offer (the "Offer") to sell such Equity Securities (the
"Offered Shares"), first to the Company, and second to the Holders, on the same
terms and conditions on which the Seller proposes to sell such Offered Shares to
the Proposed Transferee. The parties acknowledge and agree that any Transfer
described in the last sentence of Sections 3.3(a) and 3.4(a) shall not be
subject to

                                      10


the terms of this Section. The Offer shall disclose the identity of the Proposed
Transferee, the Offered Shares proposed to be sold, the terms and conditions,
including price, of the proposed sale, and any other material facts relating to
the proposed sale. The Offer shall further state that the Company and the
Holders may acquire, in accordance with the provisions of this Agreement, all or
any portion of the Offered Shares for the price and upon the other terms and
conditions, including deferred payment (if applicable), set forth therein.

          (b)  Upon receipt of the Offer, if the Company desires to purchase all
or any part of the Offered Shares, the Company shall communicate in writing its
election to purchase to the Seller, which communication shall state the number
of Offered Shares the Company desires to purchase and shall be given to the
Seller in accordance with Section 5.4 below within thirty (30) days of the date
the Offer was made. Such notice shall, when taken in conjunction with the Offer,
be deemed to constitute a valid, legally binding and enforceable agreement for
the sale to, and purchase by, the Company of the number of Offered Shares
specified by the Company in such notice and on the terms of the Offer. Sales of
the Offered Shares to be sold to the Company pursuant to this Section 3.5(b)
shall be made at the offices of the Company on the 45th day following the date
the Offer was made (or if such 45th day is not a Business Day, then on the next
succeeding Business Day). Such sales shall be effected by the Seller's delivery
to the Company of a certificate or certificates evidencing the Offered Shares to
be purchased by it, duly endorsed for transfer to the Company, against payment
to the Seller of the purchase price therefor by the Company.

          (c)  Each Holder shall, subject to the prior purchase right of the
Company, have the absolute right to purchase that number of Offered Shares not
purchased by the Company as shall be equal to the number of Offered Shares not
purchased by the Company multiplied by a fraction, the numerator of which shall
be the number of shares of Common Stock (determined on an as converted basis)
then owned by such Holder and the denominator of which shall be the aggregate
number of shares of Common Stock (determined on an as converted basis) then
owned by all of the Holders. The amount of Offered Shares that each Holder is
entitled to purchase under this Section 3.5(c) shall be referred to as its "Pro
Rata Fraction." The Holders shall have a right of oversubscription such that if
any Holder fails to accept the Offer as to its Pro Rata Fraction, the other
Holders shall, among them, have the right to purchase up to the balance of the
Offered Shares not so purchased. Such right of oversubscription may be exercised
by a Holder by accepting the Offer as to more than its Pro Rata Fraction. If, as
a result thereof, such oversubscriptions exceed the total number of Offered
Shares available in respect of such oversubscription privilege, the
oversubscribing Holders shall be cut back with respect to their
oversubscriptions on a pro rata basis in accordance with their respective Pro
Rata Fractions or as they may otherwise agree among themselves. If a Holder
desires to purchase all or any portion of the Offered Shares, said Holder shall
communicate in writing its election to purchase to the Seller and the Company,
which communication shall state the number of Offered Shares said Holder desires
to purchase and shall be given to the Seller in accordance with Section 5.4
below within thirty (30) days of the date the Offer was made. Such communication
shall, when taken in conjunction with the Offer, be deemed to constitute a
valid, legally binding and enforceable agreement for the sale and purchase of
such Offered Shares (subject to the

                                      11


aforesaid limitations as to a Holder's right to purchase more than its Pro Rata
Fraction) and on the terms of the Offer. Sales of the Offered Shares to be sold
to purchasing Holders pursuant to this Section 3.5(c) shall be made at the
offices of the Company on the later of (i) the 45th day following the date the
Offer was made (or if such later of (i) the 45th day is not a Business Day, then
on the next succeeding Business Day) and (ii) the third Business Day following
receipt of all material governmental or other consents in connection with such
sale. Such sales shall be effected by the Seller's delivery to each purchasing
Holder of a certificate or certificates evidencing the Offered Shares to be
purchased by it, duly endorsed for transfer to such purchasing Holder, against
payment to the Seller of the purchase price therefor by such purchasing Holder.

          (d)  If the Holders and the Company do not purchase in the aggregate
all of the Offered Shares, the Offered Shares not so purchased may be sold by
the Seller at any time within 90 days after the date the Offer was made, subject
to the provisions of Section 3.6 hereof. Any such sale shall be to the Proposed
Transferee, at the price and upon the other terms and conditions specified in
the Offer. Any Offered Shares not sold within such 90-day period shall continue
to be subject to the requirements of a prior offer pursuant to this Section 3.5.
If Offered Shares are sold pursuant to this Section 3.5 to any purchaser who is
not a party to this Agreement, the Offered Shares so sold shall no longer be
subject to this Agreement.

          (e)  The provisions of this Section 3.5 shall terminate upon the
earlier of: (i) a Qualified Public Offering and (ii) the time at which the
Investor Stockholders and the other Holders own less than 20% of the Common
Stock (on an as converted basis) that the Investor Stockholders owned as of the
Closing.

     SECTION 3.6    Right of Participation in Sales by Stockholders.
                    -----------------------------------------------

          (a)  If at any time any of the Stockholders (the "Tag-Along Seller")
  desires to Transfer all or any part of the Equity Securities (other than
  pursuant to Permitted Sales) owned by such Tag-Along Seller to any Person
  other than Investor Stockholders (including the other Holders) (the "Buyer"),
  the Investor Stockholders shall, except as provided below, have the right to
  sell to the Buyer, as a condition to such sale by Tag-Along Seller, at the
  same price per share and on the same terms and conditions as involved in such
  sale by the Tag-Along Seller, a number of shares of Common Stock (on an as
  converted basis) equal to the number derived from multiplying the total number
  of shares of Common Stock (on an as converted basis) proposed to be sold by
  the Tag-Along Seller by a fraction, the numerator of which is the total number
  of shares of Common Stock (on an as converted basis) held by the Investor
  Stockholders and the denominator of which is the total number of shares of
  Common Stock (on an as converted basis) held by the Tag-Along Seller and the
  Investor Stockholders (including the other Holders). The parties acknowledge
  and agree that any Transfer described in the last sentence of Sections 3.3(a)
  and 3.4 (a) shall not be subject to the terms of this Section.

          (b)  Each Investor Stockholder wishing to so participate in any sale
  under this Section 3.6 shall notify the Tag-Along Seller in writing of such
  intention within twenty (20) days after the date of their receipt of the
  Offer.

                                      12


          (c)  The Tag-Along Seller and each participating Investor Stockholder
  shall sell to the Buyer all, or at the option of the Buyer any part, of the
  Equity Securities proposed to be sold by them at the price and upon other
  terms and conditions contained in the Offer provided by the Tag-Along Seller
  under Section 3.5 above; provided, however, that any purchase of less than all
  of such Equity Securities by the Buyer shall be made from the Tag-Along Seller
  and each participating Investor Stockholder pro rata based upon the relative
  amount of the Equity Securities that the Tag-Along Seller and each
  participating Investor Stockholder is otherwise entitled to sell pursuant to
  Section 3.6(a).

          (d)  The provisions of this Section 3.6 shall terminate upon a
  Qualified Public Offering.

     SECTION 3.7    Right of Participation in Sales by Investor Stockholders.
                    --------------------------------------------------------

          (a)  If at any time the Investor Stockholders desire to Transfer at
  least 40% of the Equity Securities owned in the aggregate by them and their
  Affiliates to any Person other than an Affiliate of the Investor Stockholders
  (the "Tag-Along Purchaser"), each of the other Stockholders, shall have the
  right to sell to the Tag-Along Purchaser, as a condition to such sale by the
  Investor Stockholders, at the price per share and on the terms and conditions
  applicable to the Common Stock set forth in the Tag-Along Purchaser's offer to
  the Investor Stockholders (the "Tag-Along Purchase Offer"), a number of shares
  of Common Stock equal to the number derived from multiplying the total number
  of shares of Common Stock (on an as converted basis) proposed to be sold by
  the Investor Stockholders by a fraction, the numerator of which is the total
  number of shares of Common Stock (on an as converted basis) held by such
  Stockholder and the denominator of which is the total number of shares of
  Common Stock (on an as converted basis) held by all Stockholders and the
  Investor Stockholders.

          (b)  Each Stockholder wishing to so participate in any sale under this
  Section 3.7 shall notify the Agent in writing of such intention within twenty
  (20) days after the date such Stockholder's receipt of the Tag-Along Purchase
  Offer.

          (c)  The Investor Stockholders and each participating Stockholder
  shall sell to the Tag-Along Purchaser all, or at the option of the Tag-Along
  Purchaser any part, of the Equity Securities proposed to be sold by them at
  the price per share and on the terms and conditions as set forth with respect
  to each class and series of Capital Stock in the Tag-Along Purchaser Offer;
  provided, however, that any purchase of less than all of such Equity
  Securities by the Tag-Along Purchaser shall be made from the Investor
  Stockholders and each participating Stockholder pro rata based upon the
  relative amount of the Equity Securities that the Investor Stockholder
  (including the other Holders) and each participating Stockholder is otherwise
  entitled to sell pursuant to Section 3.7(a).

          (d)  The provisions of this Section 3.7 shall terminate upon a
  Qualified Public Offering.

     SECTION 3.8    Drag-Along Rights.
                    -----------------

                                      13


          (a)  Subject to Section 3.8(c) hereof, if the Investor
  Stockholders(collectively, the "Drag-Along Transferor") approve a sale of (i)
  a majority of the outstanding shares of Common Stock on an as converted basis
  to a Bona Fide Purchaser or (ii) all or substantially all of the assets of the
  Company to a Bona Fide Purchaser (each an "Approved Sale"), whether by way of
  merger, consolidation, sale of stock or assets, or otherwise, all Stockholders
  shall consent to and raise no objections against the Approved Sale, and if the
  Approved Sale is structured as (A) a merger or consolidation of the Company or
  a subsidiary, or a sale of all or substantially all of the assets of the
  Company or a subsidiary, each Stockholder shall waive any dissenters rights,
  appraisal rights or similar rights in connection with such merger,
  consolidation or asset sale, or (B) a sale of a majority of the outstanding
  shares of Common Stock on an as converted basis the Stockholders shall agree
  to sell their respective proportionate percentages of the Common Stock on an
  as converted basis which are the subject of the Approved Sale, on the same
  terms and conditions as applicable to the Common Stock of the Drag-Along
  Transferor. The Stockholders shall take all actions reasonably requested by
  the Drag Along Transferor in connection with the consummation of the Approved
  Sale, including the execution of all agreements and such instruments and other
  actions requested by the Drag Along Transferor to provide the representations,
  warranties, indemnities, covenants, conditions, agreements, escrow agreements
  and other provisions and agreements relating to such Approved Sale; provided,
                                                                      --------
  however, that each participating Stockholder's liability under any such
  -------
  agreement or instrument shall be limited to his/her/its proportionate
  percentage of such liability (based on the number of shares of Common Stock on
  an as converted basis held by such Stockholder which are subject to the
  Approved Sale) and shall not exceed the proceeds received by such Stockholder.
  The Stockholders shall be permitted to sell their Equity Securities pursuant
  to an Approved Sale without complying with the provisions of Sections 3.1,
  3.2, 3.3, 3.4, 3.5, 3.6 and 3.7 of this Agreement.

          (b)  If the Company and/or the Drag-Along Transferor or their
  representatives, enter into any negotiation or transaction for which
  Regulation D under the Securities Act (or any similar rule or regulation then
  in effect) may be available with respect to such negotiation or transaction
  (including a merger, consolidation or other reorganization), each Stockholder
  who is not an accredited investor (as such term is defined in Rule 501 under
  the Securities Act) will, at the request of the Company or the Drag Along
  Transferor, appoint a purchaser representative (as such term is defined in
  Rule 501 under the Securities Act) reasonably acceptable to the Company and
  such Drag Along Transferor.

          (c)  At the closing of the Approved Sale, each of the Stockholders
  shall (a) execute any documents or instruments reasonably requested by the
  Bona Fide Purchaser, and (b) deliver to the Bona Fide Purchaser certificates
  for the Equity Securities, duly endorsed or accompanied by duly executed stock
  assignments separate from certificate, free and clear of all encumbrances
  (other than those created pursuant to this Agreement), against delivery by the
  Bona Fide Purchaser of the consideration (including a certified check for the
  cash portion of such consideration) for the total sales price of the Equity
  Securities being sold by such Stockholder.

                                      14


          (d) The provisions of this Section 3.8 shall terminate upon
   consummation of a Qualified Public Offering.

                                  ARTICLE IV

                        APPROVAL RIGHTS OF STOCKHOLDERS

     SECTION 4.1 Stockholder Approval Rights. The Company shall not (and the
                 ---------------------------
Investor Stockholders shall not take any action to cause the Company to) take
any action to (i) enter into any transaction, or any agreement or understanding
with the Investor Stockholders or any Affiliate of the Investor Stockholders
(other than with respect to a Transfer of Equity Securities or as contemplated
by this Agreement, the Stock Purchase Agreement or the Transaction Documents (as
defined in the Stock Purchase Agreement)) or (ii) amend, modify, change or alter
the Company's Certificate of Incorporation or By-Laws or the Certificates of
Designation in a manner adverse to the Company or holders of Common Stock,
without the written consent of the Stockholders holding a majority of the Common
Stock, on an as converted basis, held by all Stockholders which consent shall
not be unreasonably withheld or delayed.

                                   ARTICLE V

                                 MISCELLANEOUS

     SECTION 5.1 Termination. Except as otherwise provided herein, the
                 -----------
provisions of this Agreement shall terminate: (a) upon the agreement of all of
the parties hereto, (b) with respect to ITI and Shalom and their respective
permitted transferees referred to in the last sentence of Section 3.3(a) and
Casty and its permitted transferees referred to in the last sentence of Section
3.4(a), as the case may be, when such Stockholder together with such permitted
transferees owns less than 1.25% of the outstanding Common Stock (on an as
converted basis), (c) with respect to Eidelstein and his permitted transferees
referred to in the last sentence of Section 3.3(a), when Eidelstein's employment
with the Company is terminated, (d) with respect to any other Stockholder, when
such Stockholder together with its Affiliates owns less than 1.25% of the
outstanding Common Stock (on an as-converted basis), and (e) with respect to all
Investor Stockholders and Stockholders, except as expressly provided herein,
upon a Qualified Public Offering.

     SECTION 5.2 Amendments and Waivers. Except as otherwise provided herein, no
                 ----------------------
modification, amendment or waiver of any provision of this Agreement shall be
effective against the Company or any other party unless such modification,
amendment or waiver is approved in writing by the Company, the Agent, acting on
behalf of the Investor Stockholders, and the Stockholders holding a majority of
the Common Stock on an as converted basis held by all Stockholders. The failure
of any party to enforce any of the provisions of this Agreement shall in no way
be construed as a waiver of such provisions and shall not affect the right of
such party thereafter to enforce each and every provision of this Agreement in
accordance with its terms. The parties hereby consent to any amendment to this
Agreement solely to add as a party hereto any Person acquiring

                                      15


shares of Preferred Stock or Common Stock after the date hereof pursuant to the
Tutopia Put Agreement (as defined in the Stock Purchase Agreement).

     SECTION 5.3 Successors, Assigns and Transferees. This Agreement shall bind
                 -----------------------------------
and inure to the benefit of and be enforceable by the parties hereto and their
respective heirs, personal representatives, successors and permitted assigns.
This Agreement may not be assigned by any party hereto without the prior written
consent of the other parties, except as otherwise provided herein.

     SECTION 5.4 Notices. All notices required or permitted hereunder shall be
                 -------
in writing and shall be deemed effectively given: (a) upon personal delivery to
the party to be notified; (b) when sent by confirmed facsimile if sent during
normal business hours of the recipient, if not, then on the next business day;
(c) five (5) days after having been sent by registered or certified mail, return
receipt requested, postage prepaid; or (d) one (1) business day after deposit
with a nationally recognized overnight courier, specifying next day delivery,
with written verification of receipt. All communications shall be sent, with
respect to the Company and the Investor Stockholders, to their respective
addresses specified in the Stock Purchase Agreement (or at such other address as
any such party may specify by like notice) and, with respect to any other party,
to the address of such party as shown in the stock record books of the Company
(or at such other address as any such party may specify to all of the above by
like notice).

     SECTION 5.5 Further Assurances. At any time or from time to time after the
                 ------------------
date hereof, the parties agree to cooperate with each other, and at the request
of any other party, to execute and deliver any further instruments or documents
and to take all such further action as the other party may reasonably request in
order to evidence or effectuate the consummation of the transactions
contemplated hereby and otherwise to carry out the intent of the parties
hereunder.

     SECTION 5.6 Entire Agreement. Except as otherwise expressly set forth
                 ----------------
herein, this document, the Stock Purchase Agreement and the Registration Rights
Agreement embody the complete agreement and understanding among the parties
hereto with respect to the subject matter hereof and supersede and preempt any
prior understandings, agreements or representations by or among the parties,
written or oral, that may have related to the subject matter hereof in any way.

     SECTION 5.7 Delays or Omissions. It is agreed that no delay or omission to
                 -------------------
exercise any right, power or remedy accruing to any party, upon any breach,
default or noncompliance by another party under this Agreement, shall impair any
such right, power or remedy, nor shall it be construed to be a waiver of any
such breach, default or noncompliance, or any acquiescence therein, or of or in
any similar breach, default or noncompliance thereafter occurring. It is further
agreed that any waiver, permit, consent or approval of any kind or character on
the part of any party hereto of any breach, default or noncompliance under this
Agreement or any waiver on such party's part of any provisions or conditions of
this Agreement, must be in writing and shall be effective only to the extent
specifically set forth in such writing. All remedies, either under this
Agreement, by law, or otherwise afforded to any party, shall be cumulative and
not alternative.

                                      16


     SECTION 5.8  Governing Law; Jurisdiction; Waiver of Jury Trial. This
                  -------------------------------------------------
Agreement shall be governed by and construed and enforced in accordance with the
internal laws of the State of New York without regard to the principles of
conflicts of law thereof. Each party hereto hereby irrevocably submits to the
nonexclusive jurisdiction of the courts of the state of New York and of the
United States of America sitting in the City of New York, Borough of Manhattan,
for the adjudication of any dispute hereunder or in connection herewith or with
any transaction contemplated hereby or discussed herein, and hereby irrevocably
waives, and agrees not to assert in any suit, action or proceeding, any claim
that it is not personally subject to the jurisdiction of any such court, that
the venue thereof may not be appropriate, that such suit, action or proceeding
is improper or that this Agreement or any of the documents referred to in this
Agreement may not be enforced in or by said courts, and each party hereto
irrevocably agrees that all claims with respect to such suit, action or
proceeding may be heard and determined in such a New York state or federal
court. Each party hereby irrevocably waives personal service of process and
consents to process being served in any such suit, action or proceeding by
mailing a copy thereof to such party in the manner provided in Section 12(b) of
the Stock Purchase Agreement and agrees that such service shall constitute good
and sufficient service of process and notice thereof. Nothing contained herein
shall be deemed to limit in any way any right to serve process in any manner
permitted by law. EACH PARTY HEREBY IRREVOCABLY WAIVES ANY RIGHT IT MAY HAVE,
AND AGREES NOT TO REQUEST, A JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE
HEREUNDER OR IN CONNECTION HEREWITH OR ARISING OUT OF THIS AGREEMENT OR ANY
TRANSACTION CONTEMPLATED HEREBY.

     SECTION 5.9  Severability. Whenever possible, each provision of this
                  ------------
Agreement shall be interpreted in such manner as to be effective and valid under
applicable law, but if any provision of this Agreement is held to be invalid,
illegal or unenforceable in any respect under any applicable law or rule in any
jurisdiction, such invalidity, illegality or unenforceability shall not affect
any other provision or any other jurisdiction, but this Agreement shall be
reformed, construed and enforced in such jurisdiction as if such invalid,
illegal or unenforceable provision had never been contained herein.

     SECTION 5.10 Enforcement. Each party hereto acknowledges that money damages
                  -----------
would not be an adequate remedy in the event that any of the covenants or
agreements in this Agreement are not performed in accordance with its terms, and
it is therefore agreed that in addition to and without limiting any other remedy
or right it may have, the non-breaching party will have the right to an
injunction, temporary restraining order or other equitable relief in any court
of competent jurisdiction enjoining any such breach and enforcing specifically
the terms and provisions hereof.

     SECTION 5.11 Titles and Subtitles. The titles of the sections and
                  --------------------
subsections of this Agreement are for convenience of reference only and are not
to be considered in construing this Agreement

     SECTION 5.12 Legend. Each certificate evidencing any of the shares of
                  ------
Equity Securities held by the parties hereto shall bear a legend substantially
as follows:

                                      17


          "THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO THE TERMS
          AND CONDITIONS OF THE THIRD AMENDED AND RESTATED STOCKHOLDERS
          AGREEMENT, DATED AS OF FEBRUARY 19, 2002, AS THE SAME MAY BE AMENDED,
          A COPY OF WHICH THE COMPANY WILL FURNISH TO THE HOLDER OF THIS
          CERTIFICATE UPON REQUEST AND WITHOUT CHARGE."


     SECTION 5.13 Appointment of Agent. Each of the Investor Stockholders hereby
                  --------------------
irrevocably appoints UBS (the "Agent") to act as its true and lawful agent and
attorney-in-fact and representative with full power and authority in its name,
place and stead to act on its behalf for all purposes under this Agreement. The
foregoing power of attorney is hereby declared to be irrevocable and coupled
with an interest, and such appointment includes, among other powers, the power
and authority to exercise all rights and privileges, and to discharge all
obligations, of the Investor Stockholders under this Agreement, including:

          (a) designating and removing the Investor Representatives and
  otherwise taking all actions required to be taken by the Investor Stockholders
  under Article II, including providing consents;

          (b) providing consents to Transfers under Section 3.3;

          (c) giving and receiving notices hereunder and service of process in
  any legal action or other proceedings arising out of or related to this
  Agreement and the transactions hereby; and

          (d) amending or waiving the provisions of this Agreement.

Any instructions given by the Agent hereunder shall be validly given on behalf
of each of the Investor Stockholders, and the Company shall have the right to
rely thereon. UBS hereby accepts the appointment provided for in this Agreement
and agrees to be bound by the provisions of this Agreement. All decisions and
actions by the Agent shall be binding upon each of the Investor Stockholders and
no Investor Stockholders shall have the right to object, dissent, protest or
otherwise contest the same. The Company may conclusively rely upon any action
taken by the Agent hereunder.

     SECTION 5.14 Termination of Joint Venture Agreement. By its execution
                  --------------------------------------
hereof, each of the Company, ITI, Emerging Networks, Inc. and Casty confirms
that the Subscription and Joint Venture Agreement, dated as of November 23,
1998, as amended, by and among the Company, Emerging Networks, Inc., ITI and
Casty was terminated as of June 15, 2000.

     SECTION 5.15 Stockholder's Representation.
                  ----------------------------

          (a) Each of the Stockholders severally (and not jointly) represents
  and warrants that all of the Equity Securities owned by it/him and any of
  its/his Affiliates is set forth on Exhibit A hereto and that each such
                                     ---------
  Stockholder or it/his Affiliate owns

                                      18


  such Equity Securities listed opposite its/his/their name free and clear of
  all Encumbrances (as defined in the Stock Purchase Agreement).

          (b) Each of Shalom and ITI severally (and not jointly) represents and
  warrants that Shalom controls the voting and disposition rights on all shares
  of Equity Securities owned by ITI or any of ITI's Affiliates.

     SECTION 5.16 Counterparts; Facsimile Signatures. This Agreement may be
                  ----------------------------------
executed in any number of counterparts, each of which shall be an original, but
all of which together shall constitute one instrument. This Agreement may be
executed by facsimile signature(s).



                 [Remainder of Page Intentionally Left Blank]

                                      19


     IN WITNESS WHEREOF, the parties hereto have executed the THIRD AMENDED AND
RESTATED STOCKHOLDERS AGREEMENT as of the date set forth in the first paragraph
hereof.

                                         IFX CORPORATION



                                         By:  /s/ Joel Eidelstein
                                              ---------------------------------
                                              Name:  Joel Eidelstein
                                              Title: President


                                         UBS CAPITAL AMERICAS III, L.P.

                                         By:  UBS Capital Americas III, LLC


                                              By:   /s/ Mark Lama
                                                    ---------------------------
                                              Name:  Mark Lama
                                              Title: Principal


                                              By:   /s/ Marc Unger
                                                    ---------------------------
                                              Name:  Marc Unger
                                              Title: Chief Financial Officer


                                         UBS CAPITAL LLC


                                         By:  /s/ Mark Lama
                                              ---------------------------------
                                              Name:  Mark Lama
                                              Title: Attorney-in-Fact


                                         By:  /s/ Marc Unger
                                              ---------------------------------
                                              Name:  Marc Unger
                                              Title: Attorney-in-Fact


                                         INTERNATIONAL TECHNOLOGY
                                         INVESTMENTS, LC


                                         By:  /s/ Michael Shalom
                                              ---------------------------------
                                              Name:  Michael Shalom
                                              Title: Manager

                                      20


                                         /s/ Joel Eidelstein
                                         -------------------------------------
                                         Joel Eidelstein


                                         /s/ Michael Shalom
                                         -------------------------------------
                                         Michael Shalom


                                         /s/ Lee S. Casty
                                         -------------------------------------
                                         Lee S. Casty



The provisions of Section 5.14 of
this Agreement are hereby acknowledged
and agreed to.

EMERGING NETWORKS, INC.


By:  /s/ Joel Eidelstein
    ---------------------------------------
    Name:  Joel Eidelstein
    Title: President

                                      21


                                   EXHIBIT A
                                   ---------

       Equity Securities Ownership by Stockholders and their Affiliates




              Michael Shalom                                   10,201 /(1)/
              Joel Eidelstein                                 383,245 /(2)/
              Lee S. Casty                                  2,960,282
              International Technology Investments, LC      4,500,000

(1)  Includes 10,201 shares subject to a currently exercisable option to
     purchase held by ITI
(2)  Includes 351,750 shares of Common Stock subject to an option granted to
     Eidelstein pursuant to the IFX 1998 Stock Option and Incentive Plan, which
     option currently is exercisable

                                      22