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                                                                   EXHIBIT 10.16

                           Revenue Sharing Agreement

          This Revenue Sharing Agreement (this "Agreement") dated as of August
31, 2000 is entered into by IFX Corporation (together with its subsidiaries,
"provider") and Tutopia.com, Inc. (together with its subsidiaries "customer").

          Provider is an Internet service provider offering a wide range of
services for business in Latin America. Provider and Customer have entered into
that certain Dial Access Agreement effective as of the date hereof (the "Dial
Access Agreement") under which Customer has agreed to purchase Hourly Dial
Access services from Provider in Latin America and Provider has agreed to sell
such Services to Provider. Capitalized terms used but not defined herein shall
have the meanings given to them in the Dial Access Agreement.

          In connection with providing the Services to Customer, Provider may
receive Telco Revenues (as defined below) from one or more local telephone
carriers or other telecommunications infrastructure providers ("Telcos") which
Provider has engaged to "terminate" (as such term is commonly used by
telecommunications companies) calls made by Customer's End-Users in accessing
Provider's Network. This Revenue Sharing Agreement is being entered into by the
parties in order to set forth how such Telco Revenues will be shared by Provider
and Customer.

          Accordingly, Provider and Customer hereby agree as follows:

          1.   "Telco Revenue" means any and all cash payments or credits paid
or granted by a Telco to or for the benefit of Provider as an inducement to
terminate telecommunication calls at such Telco. In connection with the
negotiation of call termination arrangements with Telcos, Provider will use its
reasonable best efforts to obtain the agreement of the Telco to provide any
consideration or benefit granted as an inducement to terminate telecommunication
calls at such Telco in the form of a direct cash payment or credit from the
Telco to Provider.

          2.   All Telco Revenues received by Provider that are based on the
number of hours and/or minutes "terminated" by Telcos as a result of Network
traffic generated by Customer pursuant to the Dial Access Agreement ("Tutopia
Generated Telco Revenues") shall be shared by Provider and Customer as follows:

          (a)  with respect to Tutopia Generated Telco Revenues generated from
               the date of this Agreement through December 31, 2000, Provider
               shall be entitled to receive 100% of Tutopia Generated Telco
               Revenues; and

          (b)  with respect to Tutopia Generated Telco Revenues generated from
               January 1, 2001 through the first (1st) anniversary of the date
               of this Agreement, Customer shall be entitled to receive 75% of
               Tutopia Generated Telco Revenues and Provider shall be entitled
               to receive 25% of Tutopia Generated Telco Revenues.

          3.   Provider shall deliver a monthly statement to Customer itemizing
all Tutopia Generated Telco Revenues reported by Telcos to Provider since the
previous statement. Such monthly statement shall be provided by Provider to
Customer as soon as practicable but in any event no later than 30 days after the
end of each calendar month.

          4.   Provider shall pay to Customer the amount of each Tutopia
Generated Telco Revenue within thirty (30) days of Provider's receipt thereof
from the applicable Telco.

          5.   From time to time Customer shall have the right to audit
Provider's records relating to the determination of Tutopia Generated Telco
Revenues (including without limitation all oral or written agreements with
Telcos relating to the termination of calls), and discuss such records with
Provider personnel, upon reasonable advance notice of no less than five (5)
business days and during normal business hours, but not more often than once in
any six (6) month period. In connection with any such audit, to the extent
reasonably requested by Customer, Provider shall use its reasonable best efforts
to provide access to the books and records of any Telco utilized by
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                                                                   EXHIBIT 10.16


Provider to "terminate" calls (to the extent such books and records relate to
the provision of services by such Telco to Provider) and to such Telco's
personnel. Customer shall bear the cost of any such audit unless it is
determined that the Tutopia Generated Telco Revenues were misstated in
Provider's favor during the period audited by more than five percent (5%), in
which case, Provider shall bear the cost of such audit. Customer shall keep all
such records (as well as any other information disclosed by Provider to Customer
pursuant to this Agreement) confidential, except as required by applicable law.

          6.   This Agreement and any issues arising out of or in relation
thereto shall be governed by the law of Florida applicable to contracts to
performed wholly within that state. Customer and Provider agree to the exclusive
jurisdiction of the courts of Florida for any action or proceeding arising out
of or in relation to this Agreement. This Agreement may be executed in
counterparts, each counterpart shall be deemed to be an original and all
counterparts individually or together shall constitute on and the same
instrument.

          7.   No partnership, agency or joint venture is intended or created by
this Agreement.

                                       IFX CORPORATION

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


                                       TUTOPIA.COM, INC.

                                       By: /s/ Jak Bursztyn
                                           ----------------
                                           Name: Jak Bursztyn
                                           Title: President


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