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                                                                   EXHIBIT 10.20

CAIXA

                         CERTIFICATE OF AMENDMENT AND RE-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. ADAUTO BARBOSA
JUNIOR, a Brazilian citizen, married, bearer of Identity Card number 292.752 -
SSP/GO, and Individual Taxpayer I.D. (CPF) number 148.888.311-49, 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 Director, Mr. JOAQUM
KIYOSHI KAVAKAMA, 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, enter this CERTIFICATE OF
AMENDMENT TO THE SERVICE AGREEMENT signed between the same parties on May 20,
2000, object of administrative process number 99.5303.033/2000, according to the
following terms and conditions:

CLAUSE 1 - PRICE

1.1      Clauses 3.5, 3.6, 3.7 and 3.8 and its sub-clauses 3.8.1 and 3.8.2 are
         abolished, and payment equivalent to one hundred million (100,000,000)
         Type 3 transactions per year is no longer due, as a result of the
         launching of new lottery games, and the second weekly draw of the
         Numbers Lotto - LOTO V - (MEGA SENA).

1.2      With the implementation of new games, the CONTRACTOR will have ensured
         a remuneration that is compatible with the performance level of the
         services rendered.

1.3      As a result of the suppression of the above-mentioned clauses, current
         clauses 3.9, 3.10, 3.11, 3.11.1, 3.12 and 3.13, will be numbered in
         sequence, 3.5, 3.6, 3.7, 3.7.1, 3.8 and 3.9, respectively.

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CLAUSE 2 - REVITALIZATION OF LOTTERY GAMES

2.1      As a counterpart to the cancellation of the Agreement clauses mentioned
         in sub-clause 1.1 above, CAIXA assumes the firm commitment to
         reformulate [now] existing games, with the purpose of making them more
         attractive, and to launch new lottery games, after carrying out a
         market research, according to the legislation in force. The launching
         schedule will be established by mutual agreement with the CONTRACTOR.

CLAUSE 3 - RATIFICATION

3.1      The Service Agreement mentioned in the caput [preamble] of this
         instrument will become effective with the amendments produced by this
         Certificate of Amendment, maintaining the clauses and conditions in
         their exact amendments that are not conflicting with the provisions of
         this instrument.

CLAUSE 4 - VENUE

4.1      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 the present Certificate of
Amendment in four (04) counterparts of equal contents and form, in the presence
of two witnesses who also sign below.

                  Brasilia-DF, September 14, 2001

                  (Signed - Illegible)
                  CAIXA ECONOMICA FEDERAL

                  (Signed - Illegible)
                  GTECH BRASIL LTDA.
                  19/09/2001

WITNESSES:

Name: Clayton da Costa Paixao
Identity Card (RG) No. 912 555 SSP/illegible

Name: Glaucio Geronasso

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Identity Card (RG) No. 1.450.217-3 SSP/PR

USU/VERAS/Amendments-GTECH-2001