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                                                                    EXHIBIT 4.15

                             ENGLISH TRANSLATION OF
                          LEASE AGREEMENT FOR PREMESIS
                        FOR USES OTHER THAN AS A DWELLING

This Commercial Lease Agreement is entered into in Barcelona this 27th day of
June 2001, BY AND BETWEEN:

Mr. JOSEP BALCELLS RABANETE, of legal age, with National Identity Card number
37,358,461-C, acting in his capacity as Chief Executive Officer and on behalf of
SERTRAM, S.A., a company with its registered address at Calle Acero 30-32,
Edificio SERTRAM, Barcelona and duly registered in the Company Registry of this
Province in Volume 3693, Book 3044 of the 2nd Section, Sheet 39,051, Folio 226,
1st Entry and with T.I.N. number A-08 475899,

Hereinafter "SERTRAM" (landlord and Owner).

AND:

Mr. JOSE IGNACIO DEL BARRIO GOMEZ of legal age, with National Identity Card
number 51,343,948-J, acting in his capacity as of a holder of a power of
attorney authorized by the Notary Public of Madrid Mr. Carlos Perez Baudin on
November 15, 2000 bearing the number 3694 of his protocol files on behalf of
CARRIERHOUSE, S.A., a company with it registered address at Calle Isabel
Colbrand, 8, Madrid and duly registered in the Companies Registry of this
province in Volume 13,891, Book 0 of the 8th Section, Sheet M-227370, Folio 164,
1st Entry and with T.I.N. number A-82232448,

Hereinafter "CARRIERHOUSE" (tenant).

Both parties mutually recognize there full legal capacity to act and the powers
of attorney with which they are empowered to execute this agreement and, for the
purposes of interpretation, the parties hereby state that this agreement has
been discussed and drafted jointly.

WITNESSETH:

1.- WHEREAS, SERTRAM is the owner of the following properties:

Description:

      a)  Office module 1(degree)-1(a) with an approximate total surface area of
          526 m(2) situated at Calle Acer 30-32 in the Barcelona Duty-Free Zone
          (Zona Franca) and registered in the Barcelona Land Registry Number 14
          in Volume 2847, Book 195, Sants-1, Folio 41, Property 9604, 1st Entry
          (as detailed in plan in ANNEX 1 attached hereto).

      b)  Office module 1(degree)-2(a) with an approximate total surface area of
          463 m(2) situated at Calle Acer 30-32 in the Barcelona Duty-Free Zone
          (Zona Franca) and registered in the Barcelona Land Registry Number 14
          in Volume 2847, Book 195, Sants-1, Folio 46, Property 9605, 1st Entry
          (as detailed in plan in ANNEX 1 attached hereto).

      c)  Premises of 720 m(2) on the ground floor situated at Calle Acer 30-32
          in the Barcelona Duty-Free Zone (Zona Franca) with three open-air
          parking spaces in the front courtyard of Calle Plomo 15, and
          registered in the Barcelona Land Registry Number 14 in Volume 2847,
          Book 195, Sants-1, Folio 36, Property 9603, 1st Entry (as detailed in
          plan in ANNEX 1 attached hereto).

      d)  Three covered parking spaces on the basement floor of Calle Acer 30-32
          in the Barcelona Duty-Free Zone (Zona Franca), numbers 13, 14 and 15,
          and registered in the Barcelona Land Registry Number 14 in Volume
          2847, Book 195, Sants-1, Folio 21, Property 9600, 1st Entry (as
          detailed in plan in ANNEX 1 attached hereto).

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      e)  Premises of 610 m(2) on the ground floor situated at situated at Calle
          Acer 30-32 in the Barcelona Duty-Free Zone (Zona Franca) and
          registered in the Barcelona Land Registry Number 14 in Volume 2847,
          Book 195, Sants-1, Folio 36, Property 9603, 1st Entry (as detailed in
          plan in ANNEX 1 attached hereto).

      f)  Courtyard surface area of approximately 25 m(2) of the Sertram
          building on Calle Acer 30-32 with entrance from Calle Plomo 16 (as
          detailed in plan in ANNEX 1 attached hereto).

      g)  Courtyard surface area of approximately 167 m(2) of the Sertram
          building on Calle Acer 30-32 with entrance from Calle Plomo 16 (as
          detailed in plan in ANNEX 1 attached hereto).

Hereinafter the "PREMISES".

All the buildings included within the streets Arenes, Hierro, Plomo and Acero
shall hereinafter be referred to as the "BUILDING";

2.- WHEREAS, CARRIERHOUSE wishes to lease the PREMISES to install in them the
elements required to perform the activities to which it is dedicated, which are
set forth in its corporate purpose and, in addition, are known and expressly
authorized hereby by SERTRAM;

3.- WHEREAS, there are a series of lease agreements that are presently in effect
which are to be annulled and replaced by this agreement upon the date of its
execution and there will thus be no discontinuity in the lease but be a
modification of some conditions having immediate effect.

The agreements to be thus substituted are the agreement entered into on January
1, 1999 concerning the aforementioned properties a), b), c) and d) and the
agreement entered into on September 7, 2000 concerning property e).

Properties f) and g) are hereby leased by CARRIERHOUSE for the first time and
incorporated into this lease agreement.

By virtue of the above, the parties enter into this commercial lease agreement,
which shall be governed by the general rules on contracting that may be
applicable, the provisions set forth in the prevailing Law on Urban Leases (Ley
de Arrendamientos Urbanos) and especially with prevalence over the
aforementioned and in as far as it is allowed by them the by following

                              TERMS AND CONDITIONS

1.- LEASE AND HANDOVER OF THE PREMISES

Subject to the terms and conditions set forth herein, SERTRAM leases the
PREMISES described in the first Whereas Clause to CARRIERHOUSE, along with all
their facilities and equipment.

CARRIERHOUSE for its part accepts the aforementioned handover and hereby states
it has received the PREMISES in a fit state for use, along with all the
necessary facilities and equipment referred to in the first paragraph of this
clause. Photographs of the PREMISES' current state are attached hereto, and
CARRIERHOUSE takes on the responsibility of maintaining the premises in the same
state up to the termination of this agreement. It likewise undertakes to replace
anything that may subsequently deteriorate more than would be expected as a
result of normal wear and tear.

CARRIERHOUSE is hereby authorized to execute any works that may be necessary for
its activities, except those that would entail modifying the structure,
retaining walls and/or facades. In order to execute installations outside the
PREMISES, CARRIERHOUSE must seek obligatory authorization from the Owner, except
when expressly authorized herein.

Consequently, SERTRAM hereby hands over to CARRIERHOUSE the keys to the PREMISES
and with them possession thereof free of occupants. It likewise takes on the
obligation of ensuring the quiet enjoyment of the PREMISES throughout the term
of this agreement.

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2.- USE OF THE PREMISES

1.1 CARRIERHOUSE shall destine the PREMISES to the following uses:

1.1.1   Premises a), b), c) and e). For its own offices and warehouses or those
        of other companies related with the activities performed by CARRIERHOUSE
        pursuant to it corporate purpose, as well as for technical premises
        refurbished for its own use and/or to provide outsourcing services to
        communications operators and to other companies, consisting of the
        housing, maintenance and, should it be the case, operation of
        communications and/or computer equipment by its own means or with the
        assistance of employees belonging to the aforementioned operators or
        companies. The foregoing shall be performed within the limits laid down
        by prevailing laws, ordinances and other applicable administrative
        regulations.

1.1.2   Premises d). For vehicle parking spaces.

1.1.3   Premises f) and g). For the installation of ancillary equipment for
        air-conditioning, electric power generating sets and power transformers.

1.2 For the purposes of the activities set forth in the previous paragraph,
    CARRIERHOUSE may sublease the PREMISES should it be necessary and shall take
    on all the obligations and entitlements arising from the LAU (Spanish
    abbreviation for Urban Leases Law). It shall also be held liable by the
    landlord for the sub-lessees, should there be any, and shall undertake to
    ensure that the sublease agreements shall automatically be terminated should
    this lease agreement be terminated. Any sublease should always be associated
    to the activities performed by CARRIERHOUSE described in the Whereas Clause
    and shall under no circumstances entail any modifications to the terms and
    conditions or clauses set forth in this agreement, or involve an increase in
    the rent set forth herein.

1.3 The tenant may not transfer the PREMISES without having received the
    landlord's express prior written consent.

1.4 The tenant shall be responsible for obtaining all the official permits to
    open and use the PREMISES. The landlord hereby undertakes to collaborate
    with the tenant to obtain such official permits by providing it with the
    necessary documents and any other support that may be necessary. The
    landlord hereby authorizes the tenant to execute any works required to
    refurbish the premises for the contractual ends set forth herein, without
    the tenant needing to apply for any subsequent authorizations in this
    regard.

1.5 The tenant expressly states hereby that it undertakes to strictly comply
    with any municipal ordinance that may affect the PREMISES' use, especially
    those concerning noise and vibrations.

1.6 The building has been granted a License of Activity (Licencia de Actividad)
    and a Finalization of Works Certificate (Certificado de fin de obras), both
    of which are attached hereto as ANNEX 5.

3.- DURATION

3.1 TERM

This agreement shall have a term of TEN (10) YEARS counting from January 1, 1999
and shall have automatic TWELVE-MONTH (12) renewal periods as of the tenth year.

Nonetheless, CARRIERHOUSE may terminate this agreement at any of the renewal
periods by giving 6 MONTHS' (6) prior notice.

Once TWENTY (20) years have elapsed from January 1, 1999, this contract shall be
definitively terminated, unless the parties should reach agreement otherwise.

3.2 VACATION

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On the date this agreement expires or terminates, whatever the cause may be,
CARRIERHOUSE shall immediately vacate the PREMISES and hand them over to SERTRAM
in the same state as they were in at the commencement of the agreement.

The PREMISES shall be handed over to SERTRAM's full satisfaction and
CARRIERHOUSE shall be responsible for any repairs that may have to be made to
return the PREMISES in a good state of upkeep, taking into account the normal
wear and tear suffered during the lease.

Once the agreement has finalized, CARRIERHOUSE shall be entitled to remove from
the PREMISES any furniture, installations or improvement works it may have made
without this being considered as a deterioration of the aforementioned PREMISES
with regard to the state in which the tenant received them.

3.3 PENALTY CLAUSE

Should the agreement be terminated and CARRIERHOUSE does not hand over the
PREMISES to SERTRAM, the former shall compensate the latter the amount of
300,000 pesetas (THREE HUNDRED THOUSAND PESETAS) for each day of delay in the
handover of the PREMISES as a compensation payment agreed upon for the damages
caused by the delay in the handover.

CARRIERHOUSE hereby reserves the right to legally deposit the keys of the
PREMISES to a notary public from the foreseen handover date.

3.4 EARLY TERMINATION

Should CARRIERHOUSE unilaterally withdraw from this agreement before the end of
the term as set forth in Clause 3.1 herein, it shall have to pay SERTRAM the
amount of the damages caused by such a withdrawal, which shall be deemed to be
equivalent to the outstanding term that has yet to transpire, unless a legal
ruling otherwise is issued.

4.- RENT

4.1 AMOUNT

The monthly rent to be paid by CARRIERHOUSE shall amount to 3,332,557 pesetas
(THREE MILLION THREE HUNDRED AND THIRTY-TWO THOUSAND FIVE HUNDRED AND
FIFTY-SEVEN PESETAS), not including the V.A.T. that may be applicable during the
term of the agreement.

The table below provides a breakdown of the monthly rent, as well as each
premises' percentage participation coefficient and the forecasts for communal
costs:

<TABLE>
<CAPTION>
                                      Percentage                Total Rent    Forecast    Total Costs
PREMISES      Use      Surface Area   Coefficient   Rent/m(2)   per Month    Costs/m(2)    per Month
--------   ---------   ------------   -----------   ---------   ----------   ----------   -----------
<S>        <C>         <C>            <C>           <C>         <C>          <C>          <C>
   a       Offices         526           3.26         1350         710,100      389         204,614
   b       Offices         463           2.87         1350         625,050      389         180,107
   c       Premises        720           3.02         1350         972,000       92          66,240
   d       Parking           -              -                       48,157
   e       Premises        610           2.58         1350         823,500       92          56,120
   f       Courtyard        25              -         1350          33,750
   g       Courtyard       167              -                      120,000
                                                                 3,332,557                  507,081
</TABLE>

4.2 PAYMENT

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Payment of the aforementioned amount shall be made one month in advance, within
the first FIVE (5) working days of each month by means of a standing order from
the account designated by CARRIERHOUSE, which hereby undertakes to notify
SERTRAM of the details thereof. The first rent instalment shall be paid from
July 1, 2001.

4.3 ARREARS

Should any of the monthly instalments not be paid, CARRIERHOUSE shall have to
pay SERTRAM an amount equivalent to the result of applying the one-year EURIBOR
interest rate increased by TWO (2) percentage points to the sum of the
outstanding amount and any unpaid interest. This shall be without prejudice to
any legal actions SERTRAM may be entitled to bring.

The aforementioned interest shall be due on a daily basis counting from the date
payment of the receipt should have been made (5th working day of each month).

4.4 UPDATING

Once the first year has elapsed, the rent shall be updated on December 1 of each
year in accordance with the upward or downward changes of the General Consumer
Price Index corresponding to the province of Barcelona set by National
Statistics Institute (Instituto Nacional de Estadistica) or the body that may
replace it. The prevailing rent for the previous year shall be used as a basis
for calculation and the percentage difference between the CPI for November of
the prior year and November of the year in which the review is to be made shall
be applied thereto.

The updating of the rent shall be applied from the date that the annual period
elapses, the first one being on January 1, 2002. Any arrears should be paid in a
one-off payment in the same month that the percentage variation of the
aforementioned index is made public.

In view of the public and objective nature of the applicable index for updating
the rent, the parties expressly agree hereby that it shall not be necessary to
give any kind of notice whatsoever of effectuate the updating of the rent agreed
upon herein.

4.5 RENT REVIEWS

Without prejudice to the updating clause agreed upon in the previous paragraph,
once FIVE (5) YEARS have elapsed from the date this agreement was entered into,
the then prevailing rent shall be reviewed either upwards or downwards to adapt
it to market rents corresponding to similar premises located in the area. Such
reviews shall have a maximum increase or decrease of 20% with regard to the last
rent paid. The market price shall be determined by the prevailing publications
issued by Real Estate Property Agents (Agentes de la Propiedad Inmobiliaria -
Spanish initials API) or by the estimates provided by three such agents of
recognised prestige.

5.- OTHER PAYMENTS

5.1 PAYMENTS CORRESPONDING TO CARRIERHOUSE

    In addition to the rent agreed upon herein, CARRIERHOUSE hereby undertakes
    to pay each of the payments set forth below in the monthly receipts:

    -   The monthly amount resulting from applying 12% per annum on the amount
        corresponding to repair works and upkeep that SERTRAM may perform to
        maintain the PREMISES and their facilities and services in a fit state
        for the uses agreed upon herein, as well as the special contribution
        percentages for improvements that may be imposed on the PREMISES or the
        BUILDING. Should such works be communal works, the amount thereof will
        be divided among all the tenants affected in accordance with the
        percentage coefficient corresponding to each premises, without it ever
        exceeding 10% of the prevailing rent.

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    -   The amount of the total costs of all the services with which the
        BUILDING is equipped, such as caretaker, cleaning, lighting of communal
        areas, 24-hour security, maintenance, the consumption of utilities
        (water, gas and electricity) by communal services and elements, power
        consumption of the BUILDING'S air-conditioning system, administration
        costs for the complex, etc. in proportion to leased property's surface
        area with regard to the building's total surface area in accordance with
        the percentage participation coefficients for communal expenses as set
        forth in the Whereas Clause contained herein.

    -   The amounts corresponding to the levying of new taxes or increases made
        to the taxable amounts or tax rates for contributions, rates and duties
        that may be levied on the property. In such an event, SERTRAM shall be
        entitled to pass on the difference between is current tax liability and
        the tax liability that may result from the levying of new taxes or the
        increase of existing taxes on the PREMISES on a 12-month pro rata basis
        after having proved to the TENANT that such taxes or increases have
        indeed come into effect.

5.2 PROVISION OF FUNDS

The communal costs set forth in the previous paragraph for 2001 are estimated to
amount to 389 pesetas/m(2) for offices and 92 pesetas/m(2) for other premises
each month.

To cover the aforementioned costs, CARRIERHOUSE shall pay a monthly provision of
funds in advance to the amount of 507,081 pesetas (FIVE HUNDRED SEVEN THOUSAND
AND EIGHTY-ONE PESETAS), not including the prevailing V.A.T., as indicated in
the table contained in Clause 4.1. Such payments shall be made within the first
five working days of each month. Once the expenses for the year in course have
been finally settled, the administrator shall proceed to determine the
difference between the costs to be paid by CARRIERHOUSE and the provision of
funds thus made. He/She shall then proceed to pay or charge for the amounts owed
or charged for in excess, as the case may be. The percentage coefficients
applicable to calculate such costs on a pro rata basis and pass them on shall be
the ones stated in the first Whereas Clause contained herein. The first payment
for this provision of funds shall be made on July 1, 2001.

5.3 SERTRAM'S LIABILITY FOR INTERRUPTIONS OF SERVICE

SERTRAM shall not be held liable for any interruptions that may occur to the
elevator, air-conditioning, central heating, etc. services during a reasonable
period of time. It shall undertake to proceed to the repair of any such faults
as soon as possible which shall never exceed 48 hours, except in cases of force
majeure and/or faults that can be imputed to electricity and water utilities.
CARRIERHOUSE shall not be entitled to withhold or delay the payment of rent nor
seek any kind of compensation, except in cases exceeding 48 hours that may be
imputed to the owner. Any incidents that result from the negligence of third
parties or serious faults whose repairs require more time shall not be
considered as imputable to the owner, even if they should exceed 48 hours. In
such cases, the owner shall demonstrate having taken all the steps at its
disposal to minimize the interruption of service.

6.- UTILITIES AND SERVICES

CARRIERHOUSE receives the PREMISES equipped with their present state of general
connections to utilities and their corresponding piping/wiring.

CARRIERHOUSE shall be responsible for the supply of water, gas, telephone and
electricity to the leased PREMISES and should therefore contract them from the
relevant utilities companies at its own cost. It shall also be responsible for:

   -  The acquisition, upkeep and repair of metering devices.

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   -  The costs for maintaining the installations of said utilities.

   -  The costs of any modifications that have been made to such installations.

SERTRAM herby undertakes to ensure that the TENANT and/or any third parties
belonging to companies related to the activities described in section 2.1
contained herein have free access to the leased PREMISES and the facilities of
the Building within which such PREMISES are located 24 hours a day throughout
the year.

7.- UPKEEP OF THE PREMISES

CARRIERHOUSE hereby states that it has received the PREMISES in a perfect state
fit for the uses to which they will be destined, along with all the facilities
and equipment described in the first Whereas Clause contained herein.
CARRIERHOUSE hereby takes on the responsibility of the PREMISES' upkeep and
likewise undertakes to carry out any repairs or replace any elements whatsoever
may be necessary for their proper upkeep, as long as they arise from
CARRIERHOUSE'S improper use of negligence.

CARRIERHOUSE shall be solely responsible for and shall wholly pay for any repair
or conservation work on the PREMISES, as well as for any such works on their
facilities needed to maintain the PREMISES in a fit state to serve for the uses
agreed upon herein, long as they arise from CARRIERHOUSE'S improper use of
negligence.

CARRIERHOUSE specifically takes on the responsibility of conserving and
maintaining locks, switches, lighting points, taps, piping, toilets, cisterns,
doors, windows, glazing and, in general, electricity, water and gas
installations. It shall be responsible for any costs derived from damages to
said elements, as long as they arise from CARRIERHOUSE'S improper use of
negligence.

8.- WORKS

CARRIERHOUSE hereby undertakes to submit a plan for the refurbishment works it
may wish to carry out prior to their execution. SERTRAM shall then proceed to
issue its approval and its express consent to said plans, without prejudice to
its entitlement to conduct a subsequent inspection of the works through the
personnel it may freely appoint. The times of the aforementioned inspections
must be agreed upon with CARRIERHOUSE no later than seven calendar days after
the finalization of the works and always in the spirit of causing the least
possible disruption to the normal activities performed in the PREMISES.

Obtaining the administrative works license for all such works shall be the sole
responsibility of CARRIERHOUSE.

Should the contractual relationship be terminated for any reason whatsoever, all
works and improvements carried out shall remain to the benefit of the PREMISES
and the Owner free of charge if CARRIERHOUSE does not remove them upon
termination of the agreement.

9.- INSURANCE

9.1 SERTRAM'S RESPONSIBILITY

SERTRAM hereby undertakes to take out and keep in effect throughout the term of
this agreement a Fire and Third-Party insurance policy from an insurance firm of
recognized solvency to cover the BUILDING.

9.2 CARRIERHOUSE'S RESPONSIBILITY

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9.2.1. Increases in the Premium

Should the premium of any of the insurance policies taken out by SERTRAM to
cover the BUILDING be increased as a result of the activities performed by
CARRIERHOUSE in the PREMISES, the latter shall be obliged to pay the former for
the increase in the premium. In order to do so, it shall be necessary for
SERTRAM to justify the effectiveness of the increase in the premium and that
such an increase is an objective increase of the risk arising from
CARRIERHOUSE's activities.

CARRIERHOUSE shall make a one-off payment to SERTRAM of said amount when it pays
for the first monthly rent due after SERTRAM pays for the annual premium.

9.2.2 Third Party Liability

In addition, CARRIERHOUSE hereby undertakes to take out and maintain in effect
throughout the term of this agreement a third party liability insurance policy
from an insurance company of recognized solvency to cover the risks of the
breakage of glazing, fire, flooding and, in general terms, all damages that may
be caused to the PREMISES or the BUILDING due to its responsibility or
negligence, as well as of its employees, collaborators and people it is
responsible for.

CARRIERHOUSE hereby undertakes to provide SERTRAM with sufficient proof of the
performance of this obligation at any moment upon the latter's request.

10.- OTHER OBLIGATIONS PERTAINING TO CARRIERHOUSE

In addition to the obligations arising from the prevailing Law on Urban Leases
(Spanish abbreviation - L.A.U.) and the clauses and annexes contained herein,
CARRIERHOUSE hereby undertakes:

   -  To take sole and direct responsibility for any damages that may be caused
      to third parties or things as a result of its activities. In any event,
      SERTRAM shall not be held liable by third parties for the reasons thus
      indicated, and shall not be held liable even for damages resulting from
      services and utilities installations.

   -  To legalize all the installations that may need obligatory prior
      authorization pursuant to prevailing safety regulations and legislation,
      as well as to comply with and perform all safety regulations that affect
      and have a bearing on its specific activities, thus undertaking to obtain
      any necessary authorizations.

   -  To facilitate access to and the inspection of the leased PREMISES to
      SERTRAM or the personnel it may appoint at any moment in order to verify
      the use and state of upkeep of the PREMISES or to execute any repairs that
      are necessary or appropriate. This shall be without entitlement to any
      compensation for any damages that may thus be caused. Such actions by
      SERTRAM or its personnel shall be performed on the dates and times agreed
      upon by the parties except for urgent works, in which case such agreement
      shall not be needed. Nonetheless, SERTRAM hereby undertakes to cause as
      little disruption as possible to CARRIERHOUSE.

   -  To dispose of and destroy any waste its activities may generate that
      cannot be withdrawn by the municipal waste disposal service.

   -  To respect any easements corresponding to gas installations: communal
      reception unit, metering room, and distribution piping to the subscribers
      within the SERTRAM Building.

   -  To comply with the BUILDING'S Internal Regulations, a copy of which it
      hereby signs as proof of its consent and attached hereto as ANNEX 2.

The breach by CARRIERHOUSE or by SERTRAM of any of the obligations agreed upon
herein shall give rise to compensation for damages and the costs shall be paid
in accordance with a judicial ruling.

11.- ADMINISTRATIVE LICENSES FOR THE OCCUPATION OF THE PREMISES

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Obtaining any administrative authorizations that may be necessary to occupy the
PREMISES and perform the activities shall be CARRIERHOUSE's responsibility and
it shall incur at its own expense all the necessary costs to obtain them.

SERTRAM for its part shall not be held liable should any of the competent
national or municipal bodies refuse to grant CARRIERHOUSE the opening or first
occupation licenses for the PREMISES, or should such licenses be withdrawn once
they have been granted, except when such an event is due to SERTRAM's
responsibility or negligence, or should it in any way be a result of its actions
or omissions.

12.- PROHIBITIONS

CARRIERHOUSE may install air-conditioning systems, electric power feeds,
satellite dishes and/or similar communications equipment or elements on the
building's terrace roof. The installation and maintenance of said equipment and
all its accessories shall be CARRIERHOUSE's sole responsibility and it must
obtain all the relevant administrative licenses that may be obligatory.
CARRIERHOUSE must likewise comply with any prevailing regulations and ordinances
that may be applicable, as well as with the rules of good construction and adopt
all the safety measures that may be required or appropriate. All the costs and
consumption that this may give rise to shall be incurred by CARRIERHOUSE.

The equipment thus installed may not produce noise, vibrations, leaks or
perturbations of any other kind whatsoever and CARRIERHOUSE shall therefore
undertake to adopt the necessary measures to avoid such situations. Upon the
termination of this agreement, CARRIERHOUSE shall remove such equipment and
ensure the roof area used is returned in its original state. Any costs that may
arise thereof shall be incurred by the Tenant, unless agreement otherwise is
reached with the owner.

The Owner shall be duly informed of the installation of the equipment described
in the paragraph above and shall have a maximum of fifteen calendar days to
issue its approval. Should this period elapse without written notice or comment
from the owner, it shall be construed that such an installation has been
authorized. If, on the contrary, the Owner gives notice against the
installation, the Owner must provide justification within the same period
stating the public or private regulations that are breached by such
installations that objectively support its denial of authorization.

CARRIERHOUSE is expressly forbidden from placing any kind of signs on the facade
or through the PREMISES' windows. CARRIERHOUSE's corporate signs may only be
located on the places indicated by SERTRAM, more specifically above the doors on
the north side of the BUILDING and they must be of the same size as the existing
signs.

CARRIERHOUSE is expressly forbidden from installing motors or machines within
the PREMISES that produce vibrations or noise that exceed the limits allowed by
municipal ordinances.

CARRIERHOUSE may not store inflammable materials, explosives and dangerous or
noxious substances within the PREMISES, except those that are necessary to
perform its authorized activities and in compliance with prevailing safety
regulations. It shall be held liable for any breaches that may be produced of
the aforementioned requirements.

CARRIERHOUSE may subrogate its position to any existing or newly set up company
belonging to ABENGOA, S.A. under the same terms and conditions as those
contained herein. It shall hereby be construed that it is expressly authorized
to do so by SERTRAM.

13.- WAIVERS OF CARRIERHOUSE

In addition to the waivers contained in other clauses of this agreement,
CARRIERHOUSE expressly waives the entitlements set forth below using the powers
granted to it in paragraph 3, Article 4 of the Urban Leases Law:

     a)  The entitlement to assign the agreement and to sublease, except for the
         cases allowed in accordance with this agreement.

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     b)  The entitlement to compensation, should it be applicable, set forth in
         Article 34 of the Urban Leases Law.

     c)  The entitlement of subrogation set forth in Article 33 of the Urban
         Leases Law.

14.- TAXES

Unless the parties reach agreement otherwise, Landlord and Tenant shall pay all
taxes, duties and other levies on the leased PREMISES that correspond to them as
set forth under the Law, except for Property Tax (Impuesto sobre Bienes
Inmuebles - IBI) and the Tax on Access Rights (Impuesto sobre Vados) which are
already passed on in the communal costs.

15.- SPECIFIC TECHNICAL CONDITIONS

Any new installations shall meet the following conditions:

Any devices installed or placed into service shall comply with applicable
prevailing regulations, including visual impact regulations contained in
ordinances. Likewise, any modifications or works shall be executed pursuant to
the laws of any tier of government that may be applicable.

The installation of equipment that emits steam to the atmosphere, such as
evaporation towers, evaporating condensers, etc., is hereby forbidden.

CARRIERHOUSE shall be responsible for any works and installations it may
require, as well as the modification of existing works and installations.

Any new installations on the terrace roof shall incorporate grills, stairs and
passageways so as to facilitate the maintenance the building's roof at any
point. Likewise, such installations should leave a free space of 80 cm. along
the whole length of the building's perimeter to enable the facade to be
maintained.

All mechanical equipment shall be equipped with appropriate dampening devices so
as not to transmit vibrations to the building. The installations' load supports
shall be conducted by specially designed sub-structures to the building's
pillars.

16.- SUBSTITUTION OF THE MIBOR BY ANOTHER SIMILAR INDEX

The parties hereby state that they are aware that the interest rate agreed upon
herein that is referenced to the MIBOR may be substituted by another index
established by the relevant regulations as a result of the introduction of the
EURO during the term of this agreement. The parties hereby agree that the
aforementioned substitution shall not entail any modification whatsoever to this
agreement and that it shall not exempt or excuse them from its performance or
grant them the power to change it or unilaterally rescind it.

17.- SUBSTITUTION OF THE PESETA BY THE EURO

The parties hereby state that they are aware that the peseta will be substituted
by the EURO during the term of this agreement. When this comes about, this
agreement shall not be modified in any way whatsoever as a result of the
aforementioned substitution, nor shall it exempt or excuse the parties from its
performance or grant them the power to change it or unilaterally rescind it.

Upon the substitution of the peseta by the EURO, the amounts contained herein
and expressed in pesetas shall be substituted by the corresponding amounts in
EUROS calculated at the exchange rate set forth by the relevant regulations.

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18.- SECURITY DEPOSIT

CARRIERHOUSE hereby sets up a security deposit to the amount of 6,665,114
pesetas (SIX MILLION SIX HUNDRED AND SIXTY-FIVE THOUSAND ONE HUNDRED AND
FOURTEEN PESETAS) equivalent to two months' rent, which shall cover the payment
of rent and other payments CARRIERHOUSE may be obliged to make by virtue of this
agreement, any damages caused by the breach of contractual obligations and any
damages caused to the PREMISES. Pursuant to the Urban Leases Law, CARRIERHOUSE
likewise undertakes to increase said sum by an amount corresponding to any rent
increase that may come about.

Both parties hereby recognize that CARRIERHOUSE has already paid out the sum of
5,417,600 pesetas (FIVE MILLION FOUR HUNDRED SEVENTEEN THOUSAND SIX HUNDRED
PESETAS) as a security deposit for the leases mentioned in the third Whereas
Clause contained herein.

CARRIERHOUSE is therefore obliged to set up a security deposit to the amount of
1,247,514 pesetas (ONE MILLION TWO HUNDRED FORTY-SEVEN THOUSAND FIVE HUNDRED AND
FOURTEEN PESETAS).

19.- NOTICES

All notices, communications or summonses that CARRIEHOUSE may have to give
SERTRAM while performing or as a result of this agreement shall be delivered to
SERTRAM at the address first written above to the attention of Mr. Joan Esteve.

All notices, communications or summonses that SERTRAM may have to give
CARRIERHOUSE while performing or as a result of this agreement shall be
delivered to the following address: Calle Acer, 30, 08038 Barcelona to the
attention of Mr. Miquel Blanch.

Should either party change address during the term of this agreement or during
the time it is pending the performance of any obligations arising from it, it
shall give notice thereof to the other party.

20.- EXECUTION OF THE AGREEMENT

All taxes and other expenses that may result from the execution, performance and
termination of this agreement that cannot be individualized shall be paid on a
fifty-fifty basis by the parties. Any expenses that can be individualized, shall
be paid for by the party that has incurred them.

The parties may mutually require each other to make this agreement public. The
costs of making this agreement public shall be borne by the party that requested
it.

21.- JURISDICTION

The parties hereby agree to submit any dispute or litigation that may arise
concerning this agreement to the judges and courts of Barcelona.

IN WITNESS WHEREOF, both parties have hereunto set their hand in duplicate in
the place and at the date first mentioned above.

[bears illegible signature]        [bears illegible signature]

SERTRAM, S.A.                               CARRIERHOUSE, S.A.

                    [bears illegible signature]      [bears illegible signature]

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