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                                                                    EXHIBIT 4.11

                             ENGLISH TRANSLATION OF

                               LEASE CONTRACT FOR

                  EDIFICIO C/ VALGRANDE N(DEGREE)6. ALCOBENDAS

In Madrid, on November 15, 2000.

                                 Having Gathered

The party of the first part, VALGRAND 6, S.A., with address in Alcobendas
(Madrid), Avenida de Europa no. 18 and operating under Fiscal Identification
Number (CIF) A-80322654. The company is represented herein by Mr. Luis Calle
Gonzalez, holder of National Identity Card number 1.387.595-M, called
hereinafter "THE LESSOR", who exercises the faculties renewed in deed granted in
Alcobendas on May 29, 2000 before the Notary, Mr. Manuel Rodriguez Marin.

And the party of the second part, CARRIERHOUSE, S.A., with address at c/ Isabel
Colbrand no. 8, in Madrid, operating under Fiscal Identification Number (CIF)
A-82232448, and represented herein by Mr. Jose Ignacio del Barrio Gomez, holder
of National Identity Card number 51.343.948-J, who exercises the faculties
granted in deed of power of attorney signed before the Notary of Madrid Mr.
Carlos Perez Baudin, on November 14, 2000, Deed number 3694 in his notarial
records. Hereinafter called "THE LESSEE".

Both parties mutually recognize each other to hold sufficient legal capacity, in
the character in which they act, to enter into contract and bind themselves, and

                                   They State

1.    That on March 15, 2000 THE LESSEE signed a lease contract with the company
      SOTOHENAR, S.L. for Premises A-1, on the First story, and B, on the Second
      story, in the Building located at c/ Valgrande no. 6 in Alcobendas. Said
      contact and its annexes are attached as Appendix 1.

2     That on May 19, 2000 both parties entered into a second lease contract.
      The lease conditions of these premises are set out in the following table:

                                       1
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<TABLE>
<CAPTION>
 Story      Premises          Lessee
--------    --------    ------------------
<S>         <C>         <C>
Basement                 BBVA
First         A-1        Carrierhouse
First         A-2A       BBVA
First         A-2B       BBVA
First                    Banco de Comercio
Second        C          BBVA
Second        An.c       -
Second        B          Carrierhouse
Third         D-1A       -
Third         D-1B       -
Third         D-2A       -
Third         D-2B       -
Fourth        E-1        -
Fourth        E-2
</TABLE>

Said contact and its annexes are attached as Appendix 2.

3.    That on May 30, 2000 SOTOHENAR, S.L. transferred to the company VALGRAND
      6, S.A. the plot of land located at c/ Valgrande no. 6, together with the
      building that contains the premises that are the object of the present
      document.

4.    That prior to the transfer mentioned in Statement 3, THE LESSEE and
      previous owner of SOTOHENAR, S.L. had agreed to combine in one the two
      aforementioned lease contracts, which it now carries out in this act, the
      present LESSOR, VALGRAND 6, S.A., assuming the obligations acquired by the
      previous owner.

5.    That said agreement to combine both contracts had a deadline that expired
      on May 30, 2000, which was extended by THE LESSEE and THE LESSOR until
      September 30, 2000, by way of private document signed by both parties and
      which accompanies the present Contract as Appendix 3.

6.    That THE LESSEE is interested in leasing the whole of the aforementioned
      Building (with exception to the 165 sq.m premises leased to Banco de
      Comercio, which will be made available to THE LESSEE once the current
      lease contract with Banco de Comercio has expired), to install offices or
      storeroom facilities for itself or for other companies of Abengoa and/or
      third parties, and technical premises prepared for its own use and/or for
      outsourcing services to communications operators and other entities. These
      latter services will consist in housing, maintenance and, if appropriate,
      operation, using its own personnel or with the assistance of personnel
      from the operators or entities, of communication and/or computer
      equipment, within the limits established under Law, by-laws and any other
      applicable administrative requirements.

7.    That the LESSOR expressly declares that the Building complies with all the
      requisites and conditions required for the LESSEE to carry out its
      business activity.

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8.    In consequence, the LESSOR and the LESSEE proceed to combine both lease
      contracts in one sole contract drawn up as set out below and which will
      govern the contractual relationship between the parties, based on the
      following,

                                     Clauses

1.    DEFINITIONS

Delivery or Reception Record refers to the document signed by both parties in
acceptance or rejection of the premises and reforms delivered by the LESSOR.

Lease refers to the present Lease Contract.

Contract refers to the present document and all its appendixes.

Date of Commencement of Contract: October 1, 2000.

Building refers to the property located at calle Valgrande number 6 in
Alcobendas.

Premises refer to the different parts of the Building that are the object of the
present Contract, identified in Appendix 5.

Reforms in Communal Areas refer to those works and reforms included in Appendix
7B.

Party refers to either Valgrand 6 or Carrierhouse individually.

Parties refer to both Valgrand 6 and Carrierhouse jointly.

Pending Finishes refer to those finishes or parts thereof in the Premises or in
the communal areas that have not been completed or have been insufficiently
completed by THE LESSOR and which THE LESSEE has indicated in the Initial
Reception Record as a necessary requirement for Final Reception of the Premises
or communal area.

Surety Bond refers to the insurance cover contracted with Insurance Company as
surety for the payment of the two (2) month's rent in the terms set out in
clause 3.8.

Reforms/Adaptations and Fitting Out refer to the works to be carried out by THE
LESSEE, under its own responsibility and to its own account and which are
considered necessary and essential to start up the business activity.

2.    LEASED OBJECT

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2.1   Subject to the terms and conditions set out in the present Contract and
      its Appendixes, THE LESSOR leases to THE LESSEE, who accepts, the premises
      described in Statement 2 and further described in the plans attached as
      Appendix 5, for the latter to carry out in said premises the business
      activities described in Statement 6 of this Contract. The 165 sq.m
      premises leased to Banco de Comercio, will be made available to THE LESSEE
      once the current lease contract with Banco de Comercio has expired

2.2   THE LESSEE will have the right of use, as a complementary element to the
      leased Premises, of the one hundred and ten (110) open-air parking spaces
      and all the outside areas located within the plot on which the Building
      stands, which is identified in the plan attached as Appendix 6.

2.3   This right of use will be understood as included within the agreed rent
      and, therefore, will not give THE LESSOR the right to any further payment.

2.4   THE LESSOR leases the Premises free from charges, encumbrances and tenants
      and assumes the obligation to allow THE LESSEE the quiet enjoyment of the
      Premises and the parking spaces during the whole term of the Contract.

                                       4
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3.    CONTRACT TERM

3.1   The present Lease Contract will have a term of TWENTY (20) YEARS, to
      commence on October 1, 2000.

3.2   The Contract will be renewed for successive terms of three (3) years if,
      upon finalization of the initially agreed term, neither of the Parties
      have notified, at least one (1) year prior to said date of maturity, their
      opposition to renewal.

3.3   THE LESSEE is obliged to pay the Rent for the first seven (7) years.
      Therefore, in the event that THE LESSEE decided to terminate the lease on
      any of the leased Premises before the first seven (7) years have elapsed
      it will be obliged to notify THE LESSOR at least six (6) months in advance
      and to pay the total Rent amount corresponding to the non-elapsed period
      of said initial seven (7) year period.

3.4   Once the obligatory lease period has elapsed, if THE LESSEE wishes to
      terminate the lease on any of the Premises at any time from the beginning
      of the eighth (8th) year following the Date of Commencement of the present
      Contract and before the end of the tenth (10th) year, it shall notify this
      to THE LESSOR at least six (6) months in advance. In this case THE LESSEE
      shall pay THE LESSOR, apart from the rent for the six (6) months prior to
      the notified Contract termination date, a further amount equal to six (6)
      month's rent, in concept of agreed penalty.

3.5   As from the eleventh (11th) year following the Date of Commencement of the
      present Contract and until its expiry, if THE LESSEE wishes to give up the
      PREMISES, thus terminating the Contract, it will be required only to
      notify this to THE LESSOR six (6) months in advance of said date of
      termination and pay the rent corresponding to said six (6) months.

3.6   Handover of keys will be understood as having taken place when these are
      made available to THE LESSOR by way of deposit with a Notary, the Courts
      or through any other recordable means.

3.7   Any significant breach of the terms agreed in this Contract will give the
      party not in breach of contract the right to notify in a justifiable
      manner the party in breach of contract, granting said party a period of
      sixty (60) calendar days as from the date of such notification to rectify
      the breach.

3.8   THE LESSEE will take out and keep up to date and in effect, a Surety Bond
      Insurance equivalent to two (2) month's rent for each of the Premises for
      which THE LESSEE has accepted final delivery in the terms established
      under clause 4.1 of the present Contract. THE LESSEE declares and accepts
      that said Surety Bond shall be handed over on the first day of the month
      in which, the rent-free period having elapsed, the bond has to be
      deposited and rent payments for each of the Premises initiated.

3.9   Failure by THE LESSEE to pay the monthly rent in the terms established
      under Clause 5 of the present Contract, will give THE LESSOR the right to
      execute, with prior notification in a justifiable manner to THE LESSEE,
      the Surety Bond mentioned in the previous clause to obtain payment of the
      rent due. Execution of said Surety Bond will constitute fulfillment of THE
      LESSEE's rent payment obligation.

3.10  Should the non-paid rent amounts exceed the rent equal to two (2) month's
      rent, THE LESSOR will be empowered to terminate the present Contract and
      demand performance of that established under Clauses 3.3, 3.4 or 3.5 of
      the present Contract, as appropriate.

                                       5
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4.    DELIVERY OF THE PREMISES

4.1   The Parties accept and agree that the Premises will be handed over in two
      Stages, as follows:

      -     Initial Delivery and Reception of the Premises (Stage 1A).

            THE LESSOR will hand over the Premises on the dates and in the
            conditions set out in Appendix 7A, as long as the Parties agree that
            the Premises are handed over in an appropriate state for THE LESSEE
            to carry out the Adaptation and Fitting Out to its entire
            satisfaction and without the works of THE LESSOR producing any
            damages for THE LESSEE or interfering with the LESSEE's Adaptation
            and Fitting Out of said Premises.

            For the purpose of reception of the premises by THE LESSEE in Stage
            1A, THE LESSOR will designate a technician who, together with the
            technician designated by THE LESSEE, will accept or reject Premises
            upon completion of the works determined for each of these and always
            within a maximum period of three (3) working days following
            notification, in writing, from THE LESSOR.

            Reception of Premises shall be documented by way of the
            pre-established document using the format of the model attached in
            Appendix 8, to be signed by both Parties and contain indication of
            the Pending Finishes, upon which THE LESSEE will accept that said
            Premises are in an appropriate state to commence the Adaptation and
            Fitting out for the purpose of carrying out its business activity.

            Rejection of Premises shall be documented by way of the
            pre-established document using the format of the model attached in
            Appendix 8, to be signed by both Parties and containing THE LESSEE's
            motives for such rejection, which may not be based on any cause
            other than those that prevent it from carrying out the Adaptation
            and Fitting Out of the Premises required to commence its business
            activity.

      -     Final Delivery and Reception of the Premises (Stage 1A).

            The LESSOR will carry out final delivery of the Premises at least
            fifteen (15) days prior to the end of the rent-free period and in
            accordance with the dates indicated in the Initial Reception Record,
            as long as all the Pending Finishes detailed in the Initial Delivery
            or Reception Record have been completed and THE LESSEE can carry out
            the Adaptation and Fitting Out required for commencement of its
            business activity.

            For the purpose of final reception of the premises by THE LESSEE in
            Stage 2A, THE LESSOR will designate a technician who, together with
            the technician designated by THE LESSEE, will give final acceptance
            of the Premises upon completion of the works detailed in the Initial
            Delivery and Reception Record for each of these and always within a
            maximum period of three (3) working days following notification, in
            writing, from THE LESSOR.

            The Final Delivery or Reception of Premises shall be documented by
            way of the pre-established document using the format of the model
            attached in Appendix 8, to be signed by both Parties.

                                       6
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4.2   THE LESSOR hereby also undertakes to carry out the Works in Communal Areas
      detailed in Appendix 7B. The Parties accept and agree that each of the
      works will be handed over in two Stages, as follows:

      -     Initial Reception of the Works in Communal Areas detailed in
            Appendix 7B (Stage 1B).

            THE LESSOR will hand over the Works in Communal Areas in accordance
            with the date and conditions indicated in Appendix 7B, as long as
            the Parties agree that they are handed over in an appropriate state
            for THE LESSEE to have, to its entire satisfaction, the use and
            enjoyment of the areas required to carry out its business activity.

            For the purpose of initial reception of the Works in Communal Areas
            by THE LESSEE in Stage 1B, THE LESSOR will designate a technician
            who, together with the technician designated by THE LESSEE, will
            accept or reject Premises upon completion of the works determined
            for each of these and always within a maximum period of three (3)
            working days following notification, in writing, from THE LESSOR.

            Reception of Works in Communal Areas shall be documented by way of a
            pre-established document following the format of the model attached
            in Appendix 8, to be signed by both Parties and contain indication
            of the Pending Finishes, upon which THE LESSEE will accept that said
            Works are adequate and apt for it to have, to its entire
            satisfaction, the use and enjoyment of the areas necessary to carry
            out its business activity.

            Rejection of Works in Communal Areas shall be documented by way of
            the pre-established document using the format of the model attached
            in Appendix 8, to be signed by both Parties and containing THE
            LESSEE's motives for such rejection, which may not be based on any
            cause other than those that prevent it from carrying out its
            business activity.

      -     Final Delivery and Reception of works detailed in Appendix 7B (Stage
            2B).

            The LESSOR will carry out final delivery of the works detailed in
            Appendix 7B in accordance with the dates indicated in the Initial
            Reception Record, as long as all the Pending Finishes detailed in
            the Initial Delivery or Reception Record have been completed and THE
            LESSEE can have, to its entire satisfaction, the use and enjoyment
            of the areas required to carry out its business activity.

            For the purpose of final reception of the works detailed in Appendix
            7B by THE LESSEE in Stage 2B, THE LESSOR will designate a technician
            who, together with the technician designated by THE LESSEE, will
            give final acceptance of the Works in Communal Areas upon completion
            of the works detailed in the Initial Delivery and Reception Record
            for each of these and always within a maximum period of three (3)
            working days following notification, in writing, from THE LESSOR.

            The Final Delivery or Reception of Works in Communal Areas shall be
            documented by way of the pre-established document using the format
            of the model attached in Appendix 8, to be signed by both Parties.

4.3   THE LESSOR will carry out all the conditioning works on the exterior of
      the Building, as well as those necessary for supplying basic services to
      the leased Premises and in the form indicated in Appendix 7 of the present
      Contract.

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4.4   In the specific plans for the leased Premises, drawn up with the mutual
      agreement of the Parties, the air-conditioning connection points and
      others for connecting, in each one of the Premises, the equipment
      belonging to THE LESSEE, will be indicated.

4.5   Whilst the works described in Appendix 7 are in progress, THE LESSOR will
      allow THE LESSEE, following prior notification and consultation, to
      individualize the accesses to the Premises, as long as, apart from
      allowing the normal use of the rest of the stories of the Building, this
      is carried out in compliance with the applicable bylaws, and particularly
      with those regarding safety and fire protection.

4.6   THE LESSOR undertakes to carry out the works necessary to comply with the
      safety and fire protection regulations in the communal areas of the
      Building where the leased Premises are located. When carrying out any
      works, THE LESSOR will do so using whatsoever means to prevent any type of
      damage to Premises leased by THE LESSEE, or to the property of the latter
      or of those for which the latter is responsible, THE LESSOR, in any case,
      holding itself responsible for and taking charge of any damages caused to
      said property or to the interests of THE LESSEE.

4.7   THE LESSEE undertakes to facilitate the execution of the adaptation works
      in the Building described in Appendixes 7 and 9, and those that, due to
      technical requisites or the requirements of Organisms or Supply Companies,
      may affect the leased Premises.

4.8   The exclusive use of the restrooms located on the third and fourth stories
      of the Building are hereby included in the Lease. Until such time as the
      Premises C, A-2.A, A-2.B and the basement are made available to THE
      LESSEE, the hallways of the third and fourth stories will be used
      exclusively, in the measure in which such use may be compatible with
      access to the terrace of the Building and the safety bylaws in effect.

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5.    RENT

5.1   Both Parties, by mutual agreement, establish the amount of the rent for
      the Premises in 1,550 pesetas per month and square meter, and for the
      Basement Premises in 425 pesetas per square meter, sum that is distributed
      between the leased Premises as follows:

      -     Premises E-1: 1,550 Pta/m(2) x 4,159.89 m(2) = Pta 6,447,830.

      -     Premises E-2: 1,550 Pta/m(2) x 4,657.65 m(2) = Pta 7,219,358.

      -     Premises D-1 .A: 1,550 Pta/m(2) x 1,858.28 m(2) = Pta 2,880,334.

      -     Premises D-1 .B: 1,550 Pta/m(22) x 2,301.61 m(2) = Pta 3,567,496.

      -     Premises D-2.A: 1,550 Pta/m(2) x 2,685.41 m(2) = Pta 4,162,386.

      -     Premises D-2.B: 1,550 Pta/m(2)(x) 1,972.24 m(2) = Pta 3,056,972.

      -     Premises A.1: 1,550 Pta/m(2) x 2,480.48 m(2) = Pta 3,844,744.

      -     Premises A-2.A: 1,550 Pta/m(2) x 2,100.12 m(2) = Pta 3,255,186.

      -     Premises A-2.B: 1,550 Pta/m(2)x 2,178.80 m(2) = Pta 3,377,140.

      -     Premises B: 1,550 Pta/m(2) x 5,232.81 m(2)= Pta 8,110,856.

      -     Premises C: 11,550 Pta/m(2) x 6,952.40 m(2) = Pta 10,776,220.

      -     Premises Appendix C: 1,550 Pta/m(2) x 455.50 m(2)= Pta 706,025.

      -     Basement Premises: 425 Pta/m(2) x 7,619.00 m(2) = Pta 3,238,075.

      Given that delivery and use of the Premises is carried out in a scaled
      manner according to the schedule indicated in Appendix 10, the amount of
      the monthly rent will be agreed for each of the Premises, once the
      rent-free period established in Clause 5.2 has elapsed.

5.2   A rent-free period of TWO (2) MONTHS is established in respect of the
      payment of rent, from the date of delivery of each of the Premises in
      Stage 1, in accordance with that set out in Clause 4.1 of this Contract.

      Should any of the leased Premises, for causes attributable to THE LESSOR,
      be handed over with a delay of one (1) week in respect of the dates
      scheduled in Appendix 7A for Stages 1A and 2A established under Clause
      4.1, the Parties agree that this same period will be added to the
      rent-free period established in respect of rent payment under Clause 5.2.
      If delivery is delayed more than one (1) week, said rent-free period will
      be extended by two (2) weeks, for each week of delay. For the purpose of
      this calculation and when THE LESSOR delays delivery by more than one (1)
      week, the remaining days' delay that do not make a whole week will be
      considered as a whole week.

      Should the works referred to under Clause 4.2, Works to be carried out in
      Communal Areas of the Building, not be completed on the date scheduled and
      established in Appendix 7B, and payment of the rent established in the
      present Contract had already begun, the Parties accept that THE LESSEE
      shall suspend payment of the rent for the affected Premises for a period
      equal to two (2) weeks for every period of one (1) week that the
      aforementioned works remained incomplete and delayed in respect of the
      date established in Appendix 7B. For the purpose of this calculation and
      when THE LESSOR delays delivery by more than one (1) week, the remaining
      days' delay that do not make a whole week will be considered as a whole
      week.

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      Should the LESSEE request, in writing, that the delivery by THE LESSOR of
      any of the leased Premises or the aforementioned Works in Communal Areas
      be delayed in respect of the dates established in Appendix 7, THE LESSEE
      will pay THE LESSOR the rent in accordance with those dates, without
      prejudice to other delays due to causes attributable to THE LESSOR, in
      which case that set out in the previous paragraph will be applicable.

5.3   The monthly rent will be increased by the legally applicable VAT and will
      be paid monthly in advance (once the rent-free period has elapsed).

5.4.  As surety for the payment of rent, at the time of signing the contract
      dated May 19, THE LESSEE delivered to THE LESSOR a performance bond
      certificate guaranteeing performance of the present Contract and issued by
      Sociedad Anonima de Instalaciones de Control (Sainco), company that THE
      LESSEE declares is solvent and which is part of the Carrierhouse, S.A.
      business group.

5.5.  The rent and assimilated amounts will be paid monthly in advance, within
      the first five (5) working days of each month, and by way of debit notes
      issued by THE LESSOR and charged to the account of THE LESSEE, which the
      latter will notify the former by registered mail. THE LESSEE will deliver
      to THE LESSOR a letter of authorization for a direct debit standing order,
      addressed to the bank in which said standing order for the payments is to
      be established.

6.    RENT REVISION

6.1   The rent will be revised on June 1 each year during the term of the
      present Contract in accordance with the variations of the weighted Retail
      Price Index, according to the indexes published by the National Statistics
      Institute, or any other similar Entity that may substitute it. The first
      revision will take place on June 1, 2001.

6.2   In the event that, upon the date of the respective revisions, THE LESSOR
      does not have available the aforementioned indexes, it will continue to
      issue provisional debit notes for the last corresponding rent amounts, THE
      LESSEE settling the difference once said indexes are available and
      together with the first debit note for the revised rent. To put into
      effect the preceding stipulation it will be required that THE LESSOR give
      THE LESSEE prior notification and warning.

6.3   Once the ten (10) year term of the Contract has elapsed, if the rent being
      paid in similar buildings in the area exceeds in more than five (5)
      percent the agreed rent, including revisions, an extraordinary rent
      revision will be carried out and will serve as the basis for the following
      years, situating the rent in line with the market prices at that time.
      Unless otherwise agreed by the Parties, the amount of the revision will be
      determined by three (3) property appraisal agencies or firms agreed by the
      Parties or, in the event of failure to reach an agreement, by one
      designated by each party and a third designated by the President of the
      Real Estate Agents Society, or failing this, by the President of the
      Property Administrators' Society, the amount of the revision to be
      calculated as the arithmetic mean amount of the three (3) appraisals and
      establishing, in any case, a maximum limit of twenty-five percent (25%)
      for this revision.

7.    COMMUNAL, SERVICES AND SUPPLY EXPENSES

7.1   The rent does not include the general expenses for Communal Services in
      the Building for the concepts of general maintenance and electricity,
      security, cleaning, gardening, etc., which are to the account of THE
      LESSEE.

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7.2   The Parties agree that once each and all the works in communal elements
      established in Appendix 7B have been completed, THE LESSEE will take over
      the Building administration and assume all the Building's expenses,
      regardless of the fact that it charges THE LESSOR for the expenses
      corresponding to the services consumed by BBVA and Banco del Comercio, THE
      LESSOR being solely and exclusively responsible for obtaining payment of
      these last. Therefore, THE LESSEE shall present a budget for expenses in
      December every year, based on which the corresponding debit notes will be
      issued in concept of the services consumed by BBVA and Banco del Comercio
      until the eleventh (11th) month, at which time an adjustment will be made
      in accordance with the real consumptions.

7.3   Payment of the Property Tax (Impuesto Sobre Bienes Inmuebles) for the
      leased Premises will be to the account of THE LESSOR.

7.4   Services such as water, electricity, telephone, etc. will be contracted in
      the name of THE LESSEE, who will be responsible for their costs.

8.    USE OF THE LEASED PREMISES. ASSIGNMENT AND SUB-LETTING.

8.1   THE LESSEE shall dedicate the leased Premises to the use indicated under
      Statement 6. The parking spaces, basement, outside areas within the plot
      where the Building is located, the roofs and the terrace may be dedicated
      to uses other than their normal uses, as long as no prohibited use, or
      permitted use in a prohibited manner, is made of them.

8.2   Unless otherwise indicated by THE LESSEE, the basement will be handed over
      by THE LESSOR prepared for use as a garaging facility. Should the said
      garage space be exploited commercially by THE LESSEE through a commercial
      arrangement with any legal entity not part of Abengoa, THE LESSEE shall
      notify THE LESSOR of this circumstance upon which the rent payable for the
      square meters occupied by the garage space will immediately be changed to
      that which corresponds to the rest of the Building.

8.3   THE LESSEE expressly declares that it undertakes to comply with and
      faithfully respect the provisions of any municipal bylaws that regulate
      the use of Premises.

8.4   THE LESSEE may not assign, sub-let or transfer the lease of any of the
      leased Premises without express prior permission, in writing, from THE
      LESSOR, expressly agreeing exclusion of the first paragraph of Section 32
      of the current Rental Act (Ley de Arrendamientos Urbanos). Notwithstanding
      this:

      A)    THE LESSEE may declare as its substitute any company (existing or to
            be created) belonging to Abengoa, the present clause being held as
            express authorization from THE LESSOR in this respect.

      B)    THE LESSEE may allow other companies of Abengoa, its mother company,
            the use of the areas leased in the present Contract, without this
            being considered as a sub-let, assignment or transfer of lease under
            rental legislation, or producing any increase in the agreed rent;
            this circumstance, however, will not produce any modification in the
            contractual relationship between THE LESSEE (or the company that
            substitutes it as LESSEE under the terms of the previous paragraph)
            and THE LESSOR.

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      C)    The contracts entered into by THE LESSEE with third parties related
            to its business activity as such, that is, installation of offices
            and storeroom facilities and technical installations prepared for
            outsourcing services to communications operators and other entities
            (services that consist in housing, maintenance and, if appropriate,
            operation of communication and/or computer equipment), will in no
            case be considered as a sub-let, assignment or transfer of lease,
            nor will they modify, in any case, the contractual relationship
            between THE LESSEE and THE LESSOR.

      For the purposes of this Clause, companies belonging to Abengoa will be
      those in which Abengoa holds, directly or indirectly, a shareholding equal
      to fifty percent (50%) or more of their share capital.

9.    Placement of Installations on the Roof of the Building

      Placement or maintenance of new installations on the roof or terrace of
      the Building by THE LESSEE, as well as any accessories, will be carried
      out exclusively under THE LESSEE's own responsibility and with all the
      official permits and licenses required, observing the applicable
      regulations and bylaws and the principles of good workmanship, and
      adopting all the safety measures required under the bylaws. All the
      expenses and services consumed arising from such installations will be to
      the account of THE LESSEE.

      THE LESSEE is free to decide, without the need for any authorization from
      THE LESSOR, the use of the roof terrace for placing publicity signs.

      THE LESSEE gives its authorization, from this moment, for THE LESSEE to
      install publicity signs or direction panels that include its logo and/or
      those of companies that are customers of Carrierhouse, S.A.

10.   CONSERVATION, MAINTENANCE AND SECURITY

10.1  THE LESSEE will not require authorization from THE LESSOR to carry out
      cleaning activities, nor to carry out normal conservation activities
      within the Premises (painting, minor repairs, etc.), nor for the
      installations and fittings in the Premises that do not require masonry
      works (carpeting, dividing panels, knock-down elements, etc.).

10.2  THE LESSEE shall, at its cost, maintain the areas that make up the leased
      Premises, as well as the accessories and installations with which they are
      equipped when handed over, in a perfect state of conservation, running
      order and cleanliness, carrying out the necessary repairs for any damage
      observed in these (Premises or installations) which it may have caused.

10.3  THE LESSOR shall carry out any repairs required for the conservation of
      the Building, either using its own means or those of others, with prior
      notification to and authorization from THE LESSEE, who undertakes to give
      THE LESSOR or the persons it authorizes, access during the day and, if the
      seriousness of the accident or repairs so requires, during the night, in
      order to carry out the necessary inspections and works. For all that set
      out in this point and in particular the consequences of such works, rights
      and obligations of THE LESSEE, the provisions of the Urban Rental Act (Ley
      Arrendamientos Urbanos) will be applied.

10.4  THE LESSOR undertakes to take out and keep up to date, at its cost, during
      the whole term of the present Contract or its successive renewals, and
      with an insurance company of recognized solvency, a fire and civil
      liability insurance policy covering the Premises. THE LESSEE

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      undertakes to take out and keep up to date, at its cost, during the whole
      term of the present Contract or its successive renewals, and with an
      insurance company of recognized solvency, a civil liability insurance
      policy covering any possible damages that, through its fault or
      negligence, may be caused in the Premises by fire or flood. At any moment,
      either of the parties may oblige the other to produce the corresponding
      insurance policy or certificate, to prove fulfillment of the terms of the
      present clause.

11.   SURETY BOND

      The Surety Bond, equal to two (2) month's rent, will be handed over to THE
      LESSOR on the first day of the month in which, the rent-free period having
      expired, payment of the rent for each Premises should begin. The Surety
      Bonds established for each of the Premises are as follows:

-     Premises E-1: Surety Bond for the amount of Pta. 12,895,658.

-     Premises E-2: Surety Bond for the amount of Pta. 14,438,750.

-     Premises D-1 .A: Surety Bond for the amount of Pta. 5,760,668.

-     Premises D-1.B: Surety Bond for the amount of Pta. 7,134,990.

-     Premises D-2.A: Surety Bond for the amount of Pta. 8,324,770.

-     Premises D-2.B: Surety Bond for the amount of Pta. 6,113.944.

-     Premises A-2.A: Surety Bond for the amount of Pta. 6,510,372.

-     Premises A-2.B: Surety Bond for the amount of Pta. 6,754,280.

-     Premises C: Bond for deposit the amount of Pta. 21,552,440.

-     Premises Appendix C: Surety Bond for the amount of Pta. 1,412,050.

-     Premises Basement: Surety Bond for the amount of Pta. 6,476,150.

The Surety Bonds for Premises A-1 and B were previously handed over by THE
LESSEE and deposited with THE LESSOR.

The Surety Bonds may not be applied to the rent payments and will be returned to
THE LESSEE upon termination of the Contract, after settlement of any expenses
and payments for deterioration, if appropriate.

12.   REFORMS/ADAPTATIONS AND FITTING OUT

12.1  THE LESSOR authorizes THE LESSEE to carry out, after notifying the former
      in a justifiable manner, the works it considers necessary to adapt and fit
      out the leased Premises, once these have been handed over, and to carry
      out in the future any works necessary to maintain their adequacy for its
      needs, as long as such works do not modify the agreed uses nor damage nor
      affect the structure or safety of the Building, nor alter the communal
      elements.

12.2  Likewise, THE LESSOR undertakes to comply with (in the leased Premises)
      the current fire protection legislation and particularly Section 15.2 of
      regulation NBE-CPI-96 and Section 14 of the Community of Madrid's Fire
      Prevention Regulations dated October 18, 2000, all of this in relation to
      the fire resistance properties of the cladding panels and without taking
      into account the existing exterior walls.

12.3  THE LESSEE is specifically granted faculty (following notification to and
      authorization from THE LESSOR), to carry out the works required to install
      on the terrace or roof of the Building whatever transmission or reception
      elements for air conditioning or electricity supply, parabolic antennae,
      communications machinery or similar elements, that may be necessary for
      its business

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      activity. THE LESSOR hereby undertakes to authorize such works, as long as
      they do not cause any deterioration to the installations, structure or
      waterproofing of the roof.

12.4  THE LESSEE will not require any authorization whatsoever to carry out any
      reforms or installations necessary for its business activity that require
      masonry, electrical or plumbing works, etc., although such works must not,
      in any case, damage or deteriorate the structure or safety of the Building
      nor modify or change its communal elements, and THE LESSOR shall be
      notified of these, in advance and in a justifiable manner.

12.5  The corresponding Authorizations and Administrative Licenses required for
      the works to be carried out in the interior to adapt the Premises to the
      needs of THE LESSEE, or which, when appropriate, THE LESSEE requires in
      order to carry out its business activity, shall be requested, followed up
      and obtained by THE LESSEE.

12.6  THE LESSOR will give THE LESSEE all the necessary assistance to obtain the
      pertinent permits and licenses, providing any documentation when requested
      any other help required. In any case, THE LESSOR declares that there is no
      prohibition in existence that prevents THE LESSEE from carrying in the
      Premises the business activities authorized under the Contract signed
      between the Parties on March 15 last, as is set out in the Binding
      Consultation carried out on April 18, 2000, which is attached as Appendix
      4.

12.7  Upon termination of the Contract, THE LESSEE may remove, at its
      convenience, the elements and equipment it has used in fitting out the
      areas, as long as this does not produce any impairment to the Premises
      compared to the state in which they were handed over by THE LESSOR. Any
      improvements made in the Premises will remain as property of the owner if
      this is thus agreed with THE LESSOR or if such improvements are left in
      the Premises by THE LESSEE at the time of handing them back upon
      termination of Contract. In any case, before such elements are removed,
      THE LESSEE will inform THE LESSOR on the work involved.

13.   ADDRESSES FOR NOTIFICATIONS

For the purposes of notification, the Parties establish the following addresses:

For THE LESSOR: the address indicated in this document.

Luis Cid Calzada,

Av. Europa, 18, Alcobendas, Madrid 28108.

For THE LESSEE:

Isidoro Costillo Iciarra

C/Los Vascos, 17, Madrid 28040.

Notifications will be considered correctly carried out and fully effective when
served at the aforementioned addresses. Any change of address will come into
effect as from the date on which it is notified, in a justifiable manner with
indication of the address to be substituted.

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14.   FORMALIZATION IN PUBLIC DEED

Either of the Parties may compel the other to formalize the present Contract in
Public Deed, all the expenses and taxes arising from such formalization being to
the account of the Party that requested it.

15.   JURISDICTION AND APPLICABLE LEGISLATION

The Parties, expressly waiving any jurisdiction that may correspond, submit
themselves and the interpretation and performance of the present Contract, to
the Spanish legislation and the decision of the Courts and Tribunals of
Alcobendas.

16.   ENTIRE AGREEMENT

The present Contract constitutes the entire agreement between the Parties in
respect of its object, it substitutes all previous contracts and agreements
between the Parties and it may not be modified except by way of another later
document signed by the duly authorized representatives of the Parties.

The present Contract comes into effect on October 1 2000. In witness whereof,
the present Contract is signed, in duplicate, in the place and on the date
stated at the commencement.

VALGRAND 6, S.A.                                     CARRIEHOUSE, S.A.

Signed:                                              Signed:

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