Document:

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                                                                   EXHIBIT 10.21

CAIXA

                   CERTIFICATE OF AMENDMENT AND RATIFICATION TO SERVICE CONTRACT
                                                                 ENTERED BETWEEN
                                                     CAIXA ECONOMICA FEDERAL AND
                                                              GTECH BRASIL LTDA.

By this instrument, CAIXA ECONOMICA FEDERAL, a government-held financial
institution and private company legal entity, created and organized under the
terms of Decree Law 759 of August 12, 1969, and by Decree no. 66.303, of March
06, 1970, currently governed by the statutes approved by Decree no. 3851, of
June 27, 2001, with amendments introduced by Decree No. 3682, of August 8, 2001,
Taxpayer I.D. (CNPJ/MF) number 00.360.305/0001-04, with headquarters at the
following address: SBS, Quadra 04, Lots 3 and 4, Brasilia, Federal District,
herein represented by its National Manager for Supplies, Mr. ROGERIO KEHL, a
Brazilian citizen, judicially separated, bearer of Identity Card number 3343.299
issued by the Ministry of the Navy, and Individual Taxpayer I.D. (CPF) number
429.149.571-49, hereinafter referred to as CAIXA, and GTECH BRASIL LTDA., with
headquarters at Alameda Araguacema, 78, Barueri, State of Sao Paulo, Corporate
Taxpayer I.D. (CNPJ/MF) number 68.926.628/0001-00, herein represented by its
President, Mr. JOAQUIM KIYOSHI KAYAKAMA, a Brazilian citizen, married, engineer,
bearer of Identity Card (RG) number 8.660.082-SSP/SP and Individual Taxpayer
(CPF) number 013.782.508-00, hereinafter referred to as CONTRACTOR,

the parties have agreed to amend and ratify the Service Agreement dated May 26,
2000 ("Contract"), the Certificate of Amendment and Re-ratification signed on
April 18, 2001 ("Term No. 1") and the Certificate of Amendment and
Re-ratification signed on September 14, 2001 ("Term No. 2"), according to the
following conditions:

1.       The amount to process each Type 6 Transaction, which will include
consultation performed and the effective payment of the bill, will be sixty-five
centavos de real (R$0.65). From this date onwards, the CONTRACTOR will not
collect the amounts related to consultations performed ("isolated
consultations") or any transactions that do not result in the effective receipt
of the bill.

2.       The amount to process each Type 3 Transaction, which result in
effectively rendering services to client, will be eighteen centavos de real
(R$0.18). Denied transactions or those that are not actually completed for any
reason will not be due.

3.       Type 2 transactions, which include payment of public utility
         concessionaire bills, payment of collection slips, housing
         installments, social security (INSS) payments and miscellaneous
         agreements will remain with the same value,

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         i.e., fifteen centavos de real (R$0.15) per effectively completed
         transactions, which result in the effective rendering of services to
         client.

4.       From this date onwards, the CONTRACTOR will not charge for any type of
transactions that do not result in the effective rendering of services to
client, denied by CAIXA or not completed by any reason. It is understood that
denied transactions are all those that return a message on the terminal
informing about the impossibility of completing the service requested, which
include "password not accepted", "invalid card", "lack of available funds" and
other. As the transaction has not been completed, it is understood that it was
cancelled by the operator or by the system during any processing phase.

5        CONTRACTOR agrees that the amounts received by CAIXA related to
transactions of isolated consultation under Type 6 Transactions and also those
that were denied and did not result in effective service rendering to client,
except those made by CAIXA's account holders, during the period between May 26,
2000 and May 31, 2002, in the amount of R$1,567,914.40, will be discounted, in
equal installments, from the invoices to be issued weekly by the CONTRACTOR,
from July 08, 2002 billing onwards, in equal and consecutive installments of
R$54,066.01, with no charges and/or additional costs for the CONTRACTOR, until
January 13, 2003.

6.       Item 4.1 of the Agreement will have the following wording:

"CAIXA will pay CONTRACTOR on a weekly basis, up to the second (2nd) business
day after the end of each period of services effectively performed, such period
to be defined as being from Tuesday to Monday, by submitting the respective
invoice up to 12:00 hours (noon) of Tuesday or subsequent business day, thus
permitting payment on the subsequent business day. if the invoice is submitted
after 12:00 hours (noon), payment will be made on the second business day [after
the invoice is submitted]."

7.       Except for the items that this Certificate of Amendment modifies, the
         other terms and conditions of Term No. 1 and Term No. 2 of the
         Agreement remain unchanged.

8.       The venue of the Federal Justice, Judiciary Section of Brasilia -
         Federal District, is competent to solve any issues arising from this
         Certificate of Amendment.

IN WITNESS WHEREOF, CAIXA and CONTRACTOR sign this Certificate of Amendment in
four (04) counterparts of equal contents and form, in the presence of two
witnesses who also sign below.

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                            Brasilia (DF), July 1st, 2002

                            CAIXA ECONOMICA FEDERAL
                            Name: Rogerio Kehl
                            Title: National Manager for Supplies

                            GTECH BRASIL LTDA.
                            Name: Joaquim Kiyoshi Kavakama
                            Title: President

                            Witnesses:

                            Name: Marcelo Jose Rovai
                            Identity Card (RG) No.: 8.105.011 SSP/SP

Name: Antonio Carlos Barasuol
                            Identity Card (RG) No.: 7016429834-SSP/RS

[Authenticated Copy]<PAGE>

                                                                   EXHIBIT 10.22

CAIXA

                                    CERTIFICATE OF AMENDMENT TO SERVICE CONTRACT
                                           ENTERED INTO ON MAY 26, 2000, BETWEEN
                                                         CAIXA ECONOMICA FEDERAL
                                                          AND GTECH BRASIL LTDA.

By this instrument, CAIXA ECONOMICA FEDERAL, a government-held financial
institution, created and organized under the terms of Decree Law 759 of August
12, 1969, and by Decree no. 66.303, of March 06, 1970, currently governed by the
statues approved by Decree no. 4371, of September 12, 2002, Taxpayer I.D.
(CNPJ/MF) number 00.360.305/0001-04, with headquarters at the address: SBS,
Quadra 04, Lots 3 and 4, Brasilia, Federal District, herein represented by its
National Manager for Supplies, Mr. JOSE WILSON DE OLIVEIRA, a Brazilian citizen,
married, bearer of Identity Card number 0326768 - SSP/DF and Individual Taxpayer
I.D. (CPF) number 101.700.651-20, hereinafter referred to as CAIXA, on the one
hand, and on the other hand the company, GTECH BRASIL LTDA., with headquarters
at Alameda Araguacema, 78, Barueri, State of Sao Paulo, Corporate Taxpayer I.D.
(CNPJ/MF) number 68.926.682.0001/00, herein represented by Messrs. MARCELO JOSE
ROVAI, a Brazilian citizen, married, engineer, bearer of Identity Card (RG)
number 8.105.001-SSP/SP and Individual Taxpayer (CPF) number 978.051.908-44, and
MARCOS TADEU DE OLIVEIRA ANDRADE, a Brazilian citizen, married, engineer bearer
of Identity Card (RG) number 5.836.998 and Individual Taxpayer (CPF) number
944.179.628-04, hereinafter referred to as CONTRACTOR, according to provisions
of Clause 5, item 5.2, of the agreement signed on May 26, 2000, and in
justifications included in the CAIXA's Administrative Process No.
99.5303.033/2000, according to Resolution of the Board of Directors of CAIXA No.
224/2003, of January 13, 2003, have agreed to enter this CERTIFICATE OF
AMENDMENT to the Service Agreement dated May 26, 2000, according to the
provisions below:

CLAUSE 1 - DURATION

This CERTIFICATE OF AMENDMENT will be in force until April 14, 2003, and will
begin on January 14, 2003.

First Paragraph: The duration provided in this Clause may be extended, at
CAIXA's sole discretion, respecting the limitations of the law, for the period
of time required to completely replace the network of the CONTRACTOR by the
network of the winner(s) of the bid(s) that will occur.

Second Paragraph: During the whole period of a possible extension of the
contractual duration, contractual conditions described in the agreement signed
on

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May 26, 2000 will apply, with amendments and re-ratifications entered into on
April 18, 2001, September 14, 2001, July 01, 2002 and this Certificate of
Amendment.

CLAUSE 2 - PRICE

For the perfect carrying out of the services, CAIXA will pay to the CONTRACTOR
the same amounts agreed to in the agreement signed on May 26, 2000, amended and
re-ratified by the Certificate of Amendment and Re-ratification signed on April
18, 2001 (Certificate No. 1), Certificate of Amendment and Re-ratification
signed on September 14, 2001 (Certificate No. 2) and by the Certificate of
Amendment and Re-ratification signed on July 01, 2002 (Certificate No. 3).

CLAUSE 3 - ESTIMATED AMOUNT

The estimated amount of this certificate of amendment is thirty million reais
(R$30,000,000.00) a month, a total of ninety million reais (R$90,000,000.00),
for the ninety (90)-day period.

CLAUSE 4 - RATIFICATION

The parties to this agreement ratify the provisions object of Clauses 1
(Definitions, 2 (Object), 3 (Price), 4 (Forms of Payment), 7 (Execution of
Services), 9 (Obligations of the Contractor), 9 (Responsibilities of the
Contractor), 10 (Obligations of CAIXA), 11 (Administrative Penalties and
Sanctions), 12 (Criminal Acts/Offenses), 14. (Inspection), 15 (Taxes Levied,
Charges, Insurance, etc.), 16 (Contractual Non-performance and Termination), 17
(Confidentiality), 18 (Miscellaneous), as well as Annexes I, II, II-A, II-B,
III, IV, V, VI, VII and VIII of the Agreement signed on May 26, 2000, with the
amendments introduced therein by the Certificates of Amendment signed on April
18, 2001, September 14, 2001 and July 01, 2002. The Clauses and Conditions not
ratified by this instrument are revoked, without adverse effects to the rights
of the contracting parties.

CLAUSE 5 - BUDGETARY FUNDS

The appropriation to cover the expenses with the proposed hiring was posted in
budgetary follow up items 5605-09 - Expenses with On-Line Lotteries and 5303.11-
Carrying out expenses - Data Processing; Events No. 3581 and No. 7641; Cost
Centers Nos. 3581 and 7641, according to commitment registered at SIPEC under
No. 009/2002-MZ.

CLAUSE 6 - CONTRACTUAL GUARANTEE

For the purposes of conforming to this term, the CONTRACTOR undertakes to submit
on this date a guaranty under the modality "Performance Bond", in the

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minimum amount of four million and five hundred thousand reais (R$4,500,000.00),
to be validate by CAIXA.

First Paragraph: The CONTRACTOR undertakes to promote the immediate replacement
of the contractual guarantee not validated by CAIXA, within up to twenty-four
(24) hours, from receipt of notice to make the requested substitution, without
limitation to totally complying with its obligations and responsibilities
resulting from, deriving from or in relation to this agreement.

Second Paragraph: The guarantee, if applicable, shall be completed whenever the
amount of the contractual fine is reduced from it.

Third Paragraph: The guarantee will be released after the perfect performance of
the agreement, provided that all the contractual terms, clauses and conditions
have been fulfilled.

Fourth Paragraph: The total or partial loss of the guarantee in favor of CAIXA,
due to contractual obligations default will be lawfully carried out,
irrespectively of any in-or-out of court notice.

Fifth Paragraph: The guarantee may be replaced at any time, by notice to CAIXA,
observing the modalities provided in Law No. 8666, of June 21, 1993.

CLAUSE 7 - VENUE

The venue of the Federal Justice - Judiciary Section of Brasilia, Federal
District, is competent to solve any issues resulting from this Certificate of
Amendment.

IN WITNESS WHEREOF, CAIXA and the CONTRACTOR sign this Certificate of Amendment
in four (04) counterparts of equal contents and form, in the presence of the
witnesses who also sign below.

                  Brasilia, January 14, 2003

                  (Sgd. - illegible)
                  CAIXA ECONOMICA FEDERAL

(Sgd. - illegible)                                          (Sgd. - Illegible)
GTECH BRASIL LTDA.                                          GTECH BRASIL LTDA.

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WITNESSES:

__________________

Name:
Identity Card No.:

__________________

Name:
Identity Card No.:

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