Document:

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                                                                    Exhibit 10.4

                       AMENDED AND RESTATED PUT AGREEMENT

     AMENDED AND RESTATED PUT AGREEMENT, dated as of August 15, 2002 among IFX
CORPORATION, a Delaware corporation (the "Company"), UBS CAPITAL AMERICAS III,
L.P., a Delaware limited partnership ("UBS LP"), and UBS CAPITAL LLC, a Delaware
limited liability company (collectively with UBS LP and their respective
successors and assigns, "UBS"). Certain capitalized terms used but not otherwise
defined herein are defined in Section 1.

     WHEREAS, the Company and UBS entered into that certain Put Agreement on
February 19, 2002 (the "Original Put Agreement"); and

     WHEREAS, the Company and UBS have entered into that certain IFX Corporation
Series D Convertible Preferred Stock Purchase Agreement, dated as of February
19, 2002 (the "Preferred Stock Purchase Agreement"); and

     WHEREAS, one of the conditions to consummation of the transactions
contemplated by the Preferred Stock Purchase Agreement is the amendment and
restatement of the Original Put Agreement.

     NOW, THEREFORE, the parties hereto agree to amend and restate the Original
Put Agreement as follows:

1.   Definitions. For the purposes of this Agreement, the following terms shall
have the meanings specified below:

     (a) "Exchange Ratio" shall mean (i) with respect to each share of Tutopia
Series A Preferred Stock which is put to the Company hereunder, 0.700833 shares
of IFX Series E Preferred Stock, (ii) with respect to each share of Tutopia
Series B Preferred Stock which is put to the Company hereunder, 0.350415 shares
of IFX Series D Preferred Stock, and (iii) with respect to each share of Tutopia
Common Stock which is put to the Company hereunder, 0.700833 shares of IFX
Series E Preferred Stock.

     (b) "IFX Common Stock" shall mean the common stock, par value $.02 per
share, of the Company.

     (c) "IFX Preferred Stock" shall mean, collectively, the IFX Series D Stock
and the IFX Series E Preferred Stock.

     (d) "IFX Series D Preferred Stock" shall mean the Company's Series D
Convertible Preferred Stock set forth in the Certificate of Designation, Number,
Powers, Preferences and Relative, Participating, Optional and Other Rights of
Series D Convertible Preferred Stock filed with the Secretary of State of
Delaware on June 27, 2002, as amended from time to time.

     (e) "IFX Series E Preferred Stock" shall have the meaning set forth in
Section 3(a).

     (f) "Pro Rata Portion" shall mean a percentage of the total number of
Tutopia Shares owned by a given holder thereof equal to the percentage of the
total number of Tutopia Shares

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owned by UBS on an as-converted basis which UBS elects to sell to the Company
pursuant to a Put Option.

     (g) "Tutopia" shall mean Tutopia.com, Inc., a Delaware corporation.

     (h) "Tutopia Common Stock" shall mean the common stock, par value $.001 per
share, of Tutopia.

     (i) "Tutopia Series A Preferred Stock" shall mean the Series A Convertible
Preferred Stock, $.001 par value per share, of Tutopia.

     (j) "Tutopia Series B Preferred Stock" shall mean the Series B Convertible
Preferred Stock, $.001 par value per share, of Tutopia.

     (k) "Tutopia Shares" shall mean, collectively, shares of Tutopia Common
Stock, Tutopia Series A Preferred Stock and Tutopia Series B Preferred Stock.

     (l) "Tutopia Stockholders Agreement" shall mean the Amended and Restated
Stockholders Agreement dated as of August 31, 2000 by and among Tutopia, Latin
Guide, Inc., UBS, LSC, LLC and the other parties named therein, as amended.

2.   Put Option.

     (a) From and after the date hereof until the first (1st) anniversary of the
date of the Original Put Agreement (the "Expiration Date"), UBS shall have the
right from time to time, upon written notice thereof, specifying the Tutopia
Shares to be put (the "UBS Put Notice"), to put to the Company all or any
portion of its Tutopia Shares (the "Put Option") at a price per share equal to
the Exchange Ratio.

     (b) Within ten (10) days after each receipt of a UBS Put Notice, the
Company shall promptly make an offer to all other holders of Tutopia Shares
(other than Latin Guide, Inc.) who are parties to the Tutopia Stockholders
Agreement, by written notice thereof, to purchase a Pro Rata Portion of the
Tutopia Shares held by each such holder thereof at a price per share equal to
the Exchange Ratio and on the other terms and conditions set forth herein. UBS
and all such other holders of Tutopia Shares who deliver a put notice
(collectively with the UBS Put Notice, the "Put Notices") to the Company within
fifteen (15) days after receipt of a notice from the Company pursuant to this
Section 2(b), shall be considered to have exercised the Put Option
simultaneously as of the date the Company received the UBS Put Notice for
purposes of this Agreement.

     (c) Within thirty (30) days following the date of a UBS Put Notice, the
Company shall purchase or cause one or more of its subsidiaries to purchase and
each Seller (as defined below) shall sell to the Company the Tutopia Shares put
pursuant to the Put Notices (subject to the Sellers' complying with any rights
of first refusal or other restrictions on transfer of such Tutopia Shares).

     (d) At the closing of a purchase of Tutopia Shares pursuant this Agreement
(a "Closing"), UBS and each of the other holders of Tutopia Shares which
accepted the offer to

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purchase made pursuant to Section 2(b) (collectively with UBS, the "Sellers")
shall deliver the certificate or certificates representing the Tutopia Shares
owned by such Seller to be sold to the Company, free and clear of all liens and
encumbrances (other than pursuant to the Tutopia Stockholders Agreement), and
the Company, as payment therefor, will issue and deliver to such Seller the
appropriate number of shares of IFX Preferred Stock in the form of a single
certificate (or such greater number of certificates representing such shares as
such Seller may request), each dated the date of Closing and registered in such
Seller's name (or in the name of such Seller's nominee(s)).

     (e) At each Closing, each Seller which is not then a party to the
Stockholders Agreement or the Registration Rights Agreement (as such terms are
defined in the Preferred Stock Purchase Agreement) shall become a party to each
such agreement by executing and delivering to the Company a counterpart
signature page thereof. In addition, at each Closing, each Seller shall
represent and warrant to the Company that it is acquiring the shares of IFX
Preferred Stock for its own account, for investment purposes only, and with no
present intention of distributing, selling or otherwise disposing of them, and
each other holder of Tutopia Shares shall waive any further rights under the
Tutopia Stockholders Agreement (with respect to the Tutopia Shares put) as a
condition to participating in the Put Option. In the event that any Seller
refuses or fails to become a party to such agreements or make such
representation and warranty or otherwise fails to comply with all of the
obligations of a Seller hereunder, then such Seller shall be deemed to have
revoked the exercise of its Put Option and shall not be entitled to have its Pro
Rata Portion of Tutopia Shares purchased by the Company at the Closing. Each
Tutopia 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,
appoint a purchaser representative (as such term is defined under the Securities
Act) reasonably satisfactory to the Company and such stockholder.

3.   Covenants of the Company.  The Company hereby covenants to UBS as follows:

     (a) As soon as practicable following receipt of the UBS Put Notice, but in
any event no later than twenty (20) days thereafter, the Company shall file with
the Secretary of State of the State of Delaware a Certificate of Designation,
Number, Powers, Preferences and Relative, Participating and Other Rights (the
"IFX Series E Preferred Certificate") authorizing a new series of preferred
stock of the Company (the "IFX Series E Preferred Stock") substantially in the
form of the Series C Certificate (as defined below). The IFX Series E Preferred
Stock shall have all of the rights, preferences, privileges and restrictions of
the Company's Series C Convertible Preferred Stock (the "Series C Preferred
Stock") set forth in the Certificate of Designation, Number, Powers, Preferences
and Relative, Participating, Optional and Other Rights of Series C Convertible
Preferred Stock of the Company filed with the Secretary of State of the State of
Delaware on February 19, 2002, as amended from time to time (the "Series C
Certificate"); provided, however, that upon a bankruptcy, liquidation,
dissolution or winding up of the Company, the holders of IFX Series E Preferred
Stock shall not be entitled to receive out of the assets or funds of the Company
by reason of their ownership of such IFX Series E Preferred Stock amounts in
excess of the Stated Preference as is provided with respect to the Series C
Preferred Stock in the Series C Certificate.

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     (b) At each Closing, (i) the shares of IFX Preferred Stock to be issued and
sold to each Seller at such Closing shall have been duly authorized and, when
delivered, will be duly and validly issued and outstanding, fully paid and
nonassessable, and will be free of Encumbrances (as defined in the Preferred
Stock Purchase Agreement), (ii) the IFX Common Stock issuable upon conversion of
the IFX Preferred Stock will have been duly authorized, will have been reserved
for issuance upon conversion of the IFX Preferred Stock, and, when issued, will
be duly and validly issued and outstanding, fully paid and nonassessable and
will be free of Encumbrances, and (iii) the shares of Common Stock issuable upon
conversion of the IFX Preferred Stock to be issued and sold to such Seller at
the Closing shall have been duly listed or admitted for trading on the Nasdaq
National Market or such other stock exchange or listing service as the IFX
Common Stock is then listed or admitted for trading.

4.   Conditions to Obligations of the Sellers. The obligation of each of the
Sellers to sell its Tutopia Shares which it has agreed to sell at the Closing
pursuant to its Put Option, and the other obligations of each of the Sellers
under this Agreement, are subject to the fulfillment at or prior to the Closing
of the following conditions, any of which may be waived in writing in whole or
in part by such Seller:

     (a) Performance. The Company and each of its subsidiaries shall have
performed and complied in all material respects with all agreements, conditions
and covenants contained herein required to be performed or complied with by it
prior to or at the Closing, including without limitation the covenants set forth
in Section 3.

     (b) Absence of Litigation. (i) The consummation of the transactions
contemplated hereby shall not have been restrained, enjoined or otherwise
prohibited by any applicable law, including any order, injunction, decree or
judgment of any court or other governmental authority; (ii) no court or other
governmental authority shall have determined that any applicable law makes
illegal the consummation of the transactions contemplated hereby and no
proceeding with respect to the application of any such applicable law to such
effect shall be pending or threatened; and (iii) no proceeding shall be pending
or shall have been threatened which seeks to impose liability upon any of the
Sellers by reason of the consummation of the transactions contemplated by this
Agreement.

     (c) Consents. Such Seller and the Company shall have obtained any and all
necessary consents and governmental approvals, and shall have made any and all
filings and declarations necessary or appropriate for the consummation of the
transactions contemplated by this Agreement. In furtherance and not in
limitation of the foregoing, the requirements of the Hart-Scott-Rodino Antitrust
Improvements Act of 1976, as amended, or any foreign anti-competition, antitrust
or pre-merger notification rules and regulations, if applicable, shall have been
complied with.

     (d) Filing of Certificate. Prior to or contemporaneously with the Closing
the IFX Series E Preferred Certificate shall have been duly filed with the
Secretary of State of the State of Delaware and shall be in full force and
effect as of the Closing and shall not have been amended or modified without the
consent of UBS.

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     (e) Other Documents. The Company shall have delivered to each of the
Sellers such other documents and completed such other proceedings relating to
the transactions contemplated by this Agreement as any Seller may reasonably
request.

5.   Conditions to Obligations of the Company. The obligation of the Company to
purchase each Seller's Tutopia Shares which such Seller has agreed to sell at
the Closing pursuant to the Put Option, and the other obligations of the Company
under this Agreement with respect to such Seller, are subject to the fulfillment
at or prior to the Closing of the following conditions, any of which may be
waived in writing in whole or in part by the Company:

     (a) Performance. Such Seller shall have performed and complied in all
material respects with all agreements, conditions and covenants contained herein
required to be performed or complied with by it prior to or at the Closing.

     (b) Absence of Litigation. (i) The consummation of the transactions
contemplated hereby shall not have been restrained, enjoined or otherwise
prohibited by any applicable law, including any order, injunction, decree or
judgment of any court or other governmental authority; (ii) no court or other
governmental authority shall have determined that any applicable law makes
illegal the consummation of the transactions contemplated hereby and no
proceeding with respect to the application of any such applicable law to such
effect shall be pending or threatened; and (iii) no proceeding shall be pending
or shall have been threatened which seeks to impose liability upon the Company
or any of its subsidiaries by reason of the consummation of the transactions
contemplated by this Agreement.

     (c) Consents. The Company shall have obtained any and all material
necessary consents and governmental approvals, and shall have made any and all
material filings and declarations necessary or appropriate for the consummation
of the transactions contemplated by this Agreement. In furtherance and not in
limitation of the foregoing, the requirements of the Hart-Scott-Rodino Antitrust
Improvements Act of 1976, as amended, or any foreign anti-competition, antitrust
or pre-merger notification rules and regulations, if applicable, shall have been
complied with.

6.   General.

     (a) Transfer; Assignment. UBS may transfer or assign its rights under this
Agreement, in whole or in part.

     (b) Notices. All notices, requests and demands to or upon the respective
parties hereto to be effective shall be in the manner provided in the Preferred
Stock Purchase Agreement.

     (c) Amendments. This Agreement may not be modified, changed, amended,
terminated or abandoned except in a writing signed by UBS and the Company.

     (d) Governing Law. 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

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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 patty 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 6(b) 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.

     (e) Publicity. Except as required by applicable law or the requirements of
any securities exchange or market (in which case the text of the announcement
shall be provided to the other parties and the other parties shall be allowed
reasonable time to comment prior to dissemination to the public), no party shall
make any public announcement in respect of this Agreement or the transactions
contemplated hereby without the prior written consent of the other parties.

     (f) Entire Agreement. This Agreement contains the entire agreement and
understanding of the parties and there are no further or other agreements or
understandings, written or oral, in effect between the parties relating to the
subject matter hereof.

     (g) Further Assurances. Each party shall cooperate and take such actions as
maybe reasonably requested by another party in order to carry out the provisions
and purposes of this Agreement and the transactions contemplated hereby and
thereby.

     (h) Counterparts. This Agreement may be executed (including by facsimile
transmission) with counterpart signature pages or in one or more counterparts,
each of which shall be deemed an original but all of which together shall
constitute one and the same instrument.

     (i) Termination. This Agreement shall terminate upon the later to occur of
(i) the Expiration Date or (ii) the date of the last Closing of any Put Options
that were exercised pursuant to Put Notices that were sent prior to the
Expiration Date.

     (j) No Third Party Rights. This Agreement is not intended and shall not be
construed to create any rights in any persons other than the parties listed on
the signature page hereto, and no person shall be entitled to assert any rights
as third party beneficiary hereunder.

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     IN WITNESS WHEREOF, the parties have executed this AMENDED AND RESTATED PUT
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

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                                         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

                                       8<PAGE>

                                                                    Exhibit 10.7

                     AMENDMENT NO. 1 TO SERIES C CONVERTIBLE
                            STOCK PURCHASE AGREEMENT

     THIS AMENDMENT NO. 1 TO SERIES C CONVERTIBLE STOCK PURCHASE AGREEMENT dated
as of December 10, 2001 (this "Amendment"), is made and entered into by and
among UBS CAPITAL AMERICAS III, L.P., a Jersey, Channel Islands limited
partnership ("Americas"), UBS CAPITAL LLC, a Delaware limited liability company
("UBS Capital" and together with Americas, the "Purchasers") and IFX
CORPORATION, a Delaware corporation (the "Company").

                                    RECITALS

     WHEREAS, Purchasers and the Company are parties to that certain Series C
Convertible Stock Purchase Agreement dated as of October 11, 2001 (the "Purchase
Agreement"); and

     WHEREAS, the Company and Purchasers desire to amend the Purchase Agreement
as set forth below, which amendment has been approved by the Board of Directors
of the Company.

     NOW, THEREFORE, for valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto agree as follows:

     1.   Termination Date. Section 10(b) of the Purchase Agreement is amended
          by deleting the number "60" and substituting the number "90" therefor.

     2.   Counterparts. This Amendment may be executed in one or more
          counterparts and all such counterparts shall be deemed an original,
          shall be construed together and shall constitute one and the same
          instrument.

     3.   Choice of Law. This Amendment shall be governed by and construed in
          accordance with the laws of the State of New York without regard to
          the conflicts of law provisions thereof.

     4.   Defined Terms. Capitalized terms used and not defined herein shall
          have the meanings ascribed to such terms in the Purchase Agreement.

     5.   Continuance of Purchase Agreement. Except as provided herein, the
          terms of the Purchase Agreement shall continue in full force and
          effect.

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     IN WITNESS WHEREOF, the parties hereto have executed and delivered this
Amendment as of the first date written above.

                          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 O. Lama
                                  ----------------------------------
                                  Name:  Mark O. 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

                                       -2-

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