<Page>


                                                                    Exhibit 10.6


                                 PROMISSORY NOTE
                                 (Demand / Term)
                        (Base Rate / LIBOR / Fixed Rate)


USD 3,750,000.00                                                January 10, 2002

                  FOR VALUE RECEIVED, the undersigned (the "Borrower") hereby
promises to pay to BANCO BILBAO VIZCAYA, S.A. (the "Bank") at Elizabethan Square
George Town, Grand Cayman, Cayman Islands, B.W.I., the principal sum of
USD THREE MILLION SEVEN HUNDRED FIFTY THOUSAND 00/100 DOLLARS in lawful money of
UNITED STATES OF AMERICA and in immediately available funds:

                  [ ]  on demand,

                  [ ]        days from date
                       ----

                  [X]  on April 26, 2003
                          --------------
                          [maturity date]

                  The Borrower promises also to pay interest on the unpaid
principal hereof in like money and like funds at said office from the date
hereof until paid:

                  [X]  at the rate of11.25% per annum

                  [ ]  at the rate of    % per annum
                       above the Bank's floating Base Lending Rate

                  [ ]     %per annum above LIBOR       MONTH(s)
                       ---                       -----

provided that, on and after maturity (by acceleration or otherwise), such rate
per annum shall be 2% in excess of that which would otherwise be applicable and
provided further that the interest rate applicable hereunder shall at all times
be the lesser of (a) the rate specified herein or (b) the maximum permitted by
law. "Base Lending Rate" shall mean the rate announced by the Bank from time to
time at its Grand Cayman Office as base lending rate for domestic commercial
loans, such rate to change on the effective date of each change in the Base
Lending Rate so announced by the Bank. Interest shall be computed on the number
of days actually elapsed on the basis of a 360-day year. "LIBOR" shall mean the
interest rate per annum quoted to the Bank in the London interbank borrowing
market for deposits of U.S. dollars in such amount and for such duration as
corresponds to the loan in question.



                                       1
<Page>


                  Such interest shall be payable:

                  [ ]  monthly

                  [ ]  bimonthly

                  [X]  quarterly

                  [ ]  semiannually

                  [ ]  annually

                  [ ]  at maturity only

in arrears, commencing on the date of disbursement of the funds, upon any
prepayment hereon (to the extent accrued on the amount thereof); at maturity
(whether by acceleration or otherwise) or, if the principal hereof is due on
demand, on demand; and after maturity on demand.

                  All payments by the Borrower under this Note are to be made
without any whithholding or deduction for any and all present or future taxes,
duties, levies, fees or other charges and without any set-off or counter-claim
whatsoever. If any deduction or witholding is required in respect of any sum
payable under this Note, the Borrower shall increase the sum so that the net
amount received by the Bank after the deduction of withholding (and after the
payment of any tax or additional tax which is due as a consequence of the
increase) shall be equal to the amount which the Bank would have been entitled
to receive in the absence of any requirement to make a deduction or witholding.

                  If in connection with any loan to which the LIBOR-based
interest rate applies there shall occur any event (including but not limited to
an increase in reserve requirements) which the Bank in its sole discretion
determines would result in the Bank not receiving interest effective at the rate
specified herein, the Borrower shall pay to the Bank, on demand, such additional
amounts as may be necessary to compensate the Bank for any such deficiency.

                  Without prejudice to the Bank's right hereunder, if for any
reason it becomes unlawful or impossible for the Bank to make, maintain or fund
this Note or give effect to its obligations as contemplated by this Note, or any
of the obligations expressed as being assumed by the Borrower under this Note is
not or ceases to be valid, legal, binding and enforceable against the Borrower
in accordance with its terms, the the Bank's



                                       2
<Page>


obligations hereunder shall terminate and the Bank may, by written notice to the
Borrower, terminate this Note forthwith and demand immediate payment of, and the
Borrower will forthwith pay the Bank, all sums outstanding hereunder.

                  Upon the occurrence of any of the following specified
events of default -- (a) the Borrower shall default in the due and punctual
payment of any interest on this Note; or (b) any representation, warranty or
statement made by the Borrower herein or in writing in connection herewith,
or in any certificate or financial or other statement furnished in connection
herewith, shall be breached or shall prove to be untrue in any material
respect on the date as of which made, or shall omit to state a material fact
necessary to make such representations, warranties or statements not
misleading; or (c) the Borrower shall default in the due payment of any
indebtedness (direct or contingent) for borrowed money or evidenced by a
bond, debenture, note or other security or by an agreement of guarantee or
any holder of any such indebtedness of the Borrower (or a person acting on
their behalf) shall become entitled to cause any such indebtedness to become,
or any such indebtedness shall become, due prior to its stated maturity; or
(d) the Borrower shall suspend or discontinue its business, or shall make an
assignment for the benefit of, or composition with, creditors, or shall
become insolvent or unable or generally fail to pay its debts when due; or
the Borrower shall become a party or subject to any liquidation or
dissolution action or proceeding with respect to the Borrower or any
bankruptcy, reorganization, insolvency or other proceeding for the relief of
financially distressed debtors with respect to the Borrower, or a receiver,
liquidator,custodian or trustee shall be appointed for the Borrower or a
substantial part of its assets and, if any of the same shall occur
involuntarily as to the Borrower, it shall not be dismissed, stayed or
discharged within 60 days; or if any order for relief shall be entered
against the Borrower under Chapter 11 of the United States Code entitled
"Bankruptcy"; or the Borrower shall take any action to effect, or which
indicates its aquiescence in any of the foregoing; -- THEN due, and in any
such event, and at any time thereafter if any such event of default shall
then be continuing, the Bank may, by written notice to the Borrower, declare
the principal of, and interest on, this Note to be, whereupon the same shall
forthwith become, immediately due and payable without presentment, demand,
protest or other notice of any kind.

                  The Borrower represents and warrants that (i) all acts,
filings, conditions and things required to be done and performed


                                       3
<Page>


and to have happened (including, without limitation, the obtaining of necessary
governmental approvals) precedent to the issuance of this Note to constitute
this Note the duly authorized, legal, valid and binding obligation of the
Borrower, enforceable in accordance with its terms have been done, performed and
have happened in due and strict compliance with all applicable laws; (ii) the
issuance and performance of this Note will not violate any law, rule,
regulation, order, decree, permit, agreement or instrument to which the Borrower
is a party or is subject, or result in the imposition of any lien upon any of
the Borrower's assets; and (iii) the Borrower's financial statements delivered
to the Bank in connection herewith, if any, fairly present the financial
condition and the results of operations of the Borrower as at the end of and for
the periods covered thereby and there has been no material adverse change in the
condition (financial or otherwise) of the Borrower since the date of the last
financial statement delivered by the Borrower to the Bank.

                  This Note is secured :

                           [X]   time deposits, securities and current accounts
                                 held with the Bank.

                           [ ]   pursuant to a Security Agreement between the
                                 Bank and the Borrower, dated

                           [ ]   a guaranty of           , dated               .
                                               ---------         --------------

                           [ ]   other security, described as follows:

                                 -----------------------------------------

(together the "collateral")

If the value of the collateral falls below [the usual or agreed upon
margin][166% of the aggregate principal amount of this Note] or if for any other
reasons the Bank considers that the collateral provided is no longer sufficient
to cover its claims, the Borrower shall on first demand from the Bank, reduce
the amount of indebtedness hereunder or provide additional security to the Bank
in order to reinstate the margin within the limit required by the Bank. If the
Borrower fails to comply with the Bank's request to either reduce the
indebtedness or provide additional security within the required time limit or,
due to practical or legal grounds, it is impossible for the Bank to contact the
Borrower, all of the Borrower's obligations under this Note shall immediately
become due and payable in their entirety.


                                       4
<Page>


In addition to any general lien, right of set-off or similar right to which the
Bank, as bankers, may be entitled by law, the Bank may at any time [after demand
has been made hereunder] and without notice to the Borrower, debit any of the
Borrower's accounts with the Bank with all or any part of the aggregate
principal amount of all sums then outstanding under this Note and all other
amounts payable by the Borrower to the Bank hereunder, notwithstanding that such
debit may cause any such account to become overdrawn or cause an existing
overdraft to be increased, and/or set off or transfer any sum or sums standing
to the credit of any of the Borrower's accounts with the Bank, whether or not
the same may result in the breaking of any fixture or notice period in relation
to a credit or deposit balance, in or towards satisfaction of the Borrower's
liabilities to the Bank on any other account (whether such liability is actual
or contigient, primary or collateral, present or future, several or joint) or in
any other respect; and if such liability or any part thereof is in different
currency from any credit balance against which the Bank seeks to set it off, the
Bank shall be entitled to use the currency of such credit balance for the
purchase of an amount in the currency of the liability not exceeding the amount
of such liability and also to pay out of such credit balance any additional sum
which th Bank may be required to pay for such currency and any costs in
connection with such purchase.

                  This Note is subject to prepayment in whole or in part without
premium or penalty except in the case of a LIBOR-based loan, prepayment of which
may be subject to premium or penalty. The Borrower (i) waives presentment,
demand, protest or notice of any kind in connection with this Note and (ii)
agrees to pay to the holder hereof, on demand, all costs and expenses (including
reasonable legal fees) incurred in connection with the enforcement and
collection of this Note. This Note shall be construed in accordance with and
governed by laws of the Cayman Islands.


                  The Borrower agrees that any legal action or proceeding with
respect to this Note against the Borrower may be brought in the courts of the
Cayman Islands located in the City of George Town, Grand Cayman and that process
out of said courts may be served by mail and that such service shall be deemed
effected 10 days after mailing. Nothing herein shall affect the right of the
Bank to serve process in any other manner permitted by law or to commence legal
proceedings in any other jurisdiction.


                                       5
<Page>


Name of Borrower:


                  By (signature): /s/ EDGAR ZURCHER
                                  --------------------------------
                  Print:          EDGAR ZURCHER

                  Name of Borrower: PRICSMARLANDCO, S.A.
                                    ------------------------------
                  Title: PRESIDENT

                  Address:   SAN JOSE, COSTA RICA
                           ---------------------------------------

jurisdiction of Incorporation/
Organization (if not an individual): COSTA RICA
                                     -----------------------------


                                       6