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Commercial Lease

Between

                           Prinzenpark GbR
                           Kanzlerstr. 4
                           40472 Dusseldorf

                           - hereinafter referred to as Lessor -

arid

                           Star Telecommunications
                           Deutschland GmbH
                           BeethovenstraBe 8 - 10
                           60325 Frankfurt/Main

                           - hereinafter referred to as Lessee -

the following 1ease is signed:

                                    SECTION 1
                                 LEASED PROPERTY

1.       ACCORDING TO THE GROUND PLAN ATTACHED AS APPENDIX, which forms part of
         this Lease, Lessor grant Lessee a Lease of the following areas for the
         establishment of an office Business) within the building Prinzenallee
         7, erected on the premises Prinzenallee 5- 21/Hansaallee 101, 40549
         Duesseldorf:

A)       PRINZENALLEE 7, OFFICE AREA ON THE GROUND FLOOR OF APPROX. 1,122.12
         M(2)

B)       PRINZENALLEE 7, OFFICE AREA IN THE BASEMENT OF APPROX. 112,09 M(2)

C)       PRINZENALLEE 7, STORAGE AREA IN THE BASEMENT OF APPROX. 124.76 M(2)

D)       6 PARKING SPACES IN THE UNDERGROUND CAR PARK (NOS. 391 TO 396)

E)       2 PARKING PACES OUTSIDE (NO.29 AND 30)

2.       In the ground plans attached AS APPENDIX, the leased areas according to
         sub-paragraph 1 A) TO C) are marked in red outline and determined by
         the area between the inside of the demarcation walls of the building,
         so that possibly existing movable lightweight or partition walls and
         interior stairs as well as other similar building components are not
         deducted but regarded as leased area Non-usable traffic areas arid
         suchlike have been taken into consideration when calculating the amount
         of rent.

         The areas mentioned in sub-paragraph 1 D) AND E) are determined
         bindingly by the two parties, so that the location can be taken from
         plans as well.

         If a later measurement results in deviations of less than 2.5%, none of
         the two parties shall be entitled to demand an adjustment of rent for
         this reason.

3.       The ground p1an serves exclusively for determining the situation of the
         Leased Property.

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4.       The Leased Property is provided ACCORDING TO THE GROUND PLAN ATTACHED
         AS APPENDIX, interior works completed.

         Lessor reserves the right of minor alterations which do not interfere
         with Lessee's business operation or which are advisable on the basis of
         conditions imposed by the authorities or technical requirements.

         Lessee shall take into account the necessary escape routes when
         establishing and operating the Leased Property - if necessary according
         to Lessor's instructions - and to keep them permanently clear for
         unhindered passage.

         On the occasion of handing over, a handing over protocol shall be
         prepared. Any possible defects, considerably reducing the Leased
         Property's suitability for contractual use, are to be listed therein.
         These defects are to be remedied by Lessor within a reasonable period
         of time.

         By taking over, Lessee agrees that in other respects, the Leased
         Property is in a condition suitable for contractual use.

5.       To the extent that Lessee requires alterations to the Leased Property
         exceeding those of the present equipping and of the GROUND PLAN
         ATTACHED AS APPENDIX, these alterations are subject to Lessor's prior
         written consent in each individual case Consent may be denied for
         substantial reasons only. If consent is granted, Lessee may carry out
         these alterations at its own expense.

         Lessee shall have these works carried out in accordance with Lessor's
         supervision of works. Lessor is entitled to make its consent dependent
         on compliance with supplimentary terms.

6        Lessor does not warrant that the leased area have been designed
         according to ground plan down to the last detail.

7        The carrying capacity of the ceilings is:
         - on the ground floor                        = 500 kg/m(2)
         - on the first floor to upper story          = 350 kg/m(2)
         including Allowance for partition walls,

                                    SECTION 2
                               BEGINNING OF LEASE

1.       The Lease begins on the handing over date, probably on

                                JANUARY 1ST, 1998

2.       The contractual relationship shall begin on signing the contract, the
         Lease on handing over.

3.       The construction period required for special facilities and special
         requests of Lessee is to be regarded as rental period, unless its
         execution runs parallel to the completion to be effected by Lessor
         requiring additional time.


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                                    SECTION 3
                                DURATION OF LEASE

1.       The Lease is contracted for a duration of ten years. It begins on
         handing over.

2.       LESSOR GRANTS LESSEE THE OPTION TO RENEW THE LEASE FOR ANOTHER FIVE
         YEARS. LESSEE'S DECLARATION TO EXERCISE ITS RIGHT OF OPTION HAS TO BE
         RECEIVED BY LESSOR NOT LATER THAN 12 MONTHS PRIOR TO EXPIRY OF THE
         TENTH YEAR OF CONTRACT. THE DECLARATION MUST BE MADE IN WRITING.

3.       WHEN LESSEE REMAINS IN POSSESSION OF THE LEASED PROPERTY AFTER EXPIRY
         OF THE LEASE, THE LEASE IS NOT TO BE REGARDED AS RENEWED. SECTION 568
         GERMAN CIVIL CODE BGB IS NOT APPLICABLE. CONTINUATION OR RENEWAL OF
         LEASE AFTER ITS TERMINATION MUST BE AGREED IN WRITING.

                                    SECTION 4
                                  CANCELLATION

1.       Lessor is entitled to terminate the Lease without notice, if and when

a)       Lessee is in arrears with the payment of rent and/or payment of costs
         according to Section 6 of this contract despite written reminder, with
         a sum REACHING the amount of two monthly rents (see Section 6,
         sub-paragraph 1) or, in the case of incidental expenses, the quarterly
         payment.

b)       Lessee continues to use the property in a manner contrary to the terms
         of the Lease, or it, Lessee otherwise considerably or lastingly
         infringes the rights of Lessor or other lessees, or leaves the Property
         to a third party without authorization, and if it fails to take
         corrective action despite written caution by registered letter
         specifying a reasonable time limit.

c)       a petition in bankruptcy or for the institution of composition
         proceedings has been filed with respect to Lessee's assets, or if a
         petition in bankruptcy is dismissed for lack of assets or if Lessee has
         otherwise suspended payments or enters into extrajudicial composition
         proceedings.

d)       the contractually agreed type of use is changed without Lessor's
         consent and no corrective action is taken despite written caution by
         registered letter specifying a reasonable time limit.

2.       LESSEE IS ENTITLED TO TERMINATION OF LEASE WITHOUT NOTICE, PROVIDED
         LESSOR FAILS TO COMPLY WITH ESSENTIAL CONTRACTUAL OBLIGATIONS DESPITE
         WRITTEN CAUTION SPECIFYING A REASONABLE TIME LIMIT OR IF CIRCUMSTANCES
         AS DESCRIBED UNDER SECTION 4, SUBPARAGRAPH 1.C) ARE APPLICABLE TO
         LESSOR.

3.       The notice of termination must be given in writing. It becomes
         effective on receipt.

4.       In the case of premature termination of Lease subject to Lessee's
         responsibility, Lessee shall be liable for the loss of rent, incidental
         expenses and other payments for the contractual duration of Lease as
         well as for any other loss suffered by Lessor due to the premature
         cancellation of Lease with respect to the Leased area, unless Lessor is
         indemnified by a new, adequate lease of the rooms. THE COSTS ACCRUED IN
         THIS RESPECT (IN PARTICULAR INSERTION EXPENSES AND BROKER'S COMMISSION)
         ARE TO BE BORNE BY LESSEE. LESSOR SHALL MAKE ANY EFFORT TO FIND A
         SUITABLE NEW LESSEE. IT WILL ACCEPT A NEW LESSEE PRESENTED BY


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         LESSEE, PROVIDED THE NEW LESSEE EQUALS LESSEE WITH RESPECT TO KIND OF
         BUSINESS AND FINANCIAL SOUNDNESS.

                                    SECTION 5
                       OBLIGATIONS ON TERMINATION OF LEASE

1.      On termination of Lease on any legal ground whatsoever, Lessee shall
        return the Leased Property to Lessor in an expertly renovated and
        cleaned condition, not later than on the last calendar day of the rental
        period. The obligation to renovate does not refer to normal wear and
        tear regarding roof and compartment of the Property. IN OTHER RESPECTS,
        IT ONLY REFERS TO THOSE ITEMS CLASSIFIED AS SUBJECT TO DECORATIVE
        REPAIRS ACCORDING TO SECTION 28, SUB-PARAGRAPH 4, SENTENCE 5 II OF THE
        OPERATING AGREEMENT BV (AS AMENDED ON OCT.12, 1990), AND TO CARPETS, IF
        THESE HAD BEEN PROVIDED BY LESSOR ON MOVE.

2.      By the end of the rental period, Lessee shall have removed any
        installations and structural alterations executed by Lessee prior to or
        after moving in, and Lessee shall restore the state of the building
        originally planned or existing. If and to such an extent as allowed by
        Lessor, Lessee is entitled not to remove installations or structural
        alterations. In this case, Lessor is entitled to acquire them wholly or
        in part, against payment of a reasonable compensation. THIS DOES NOT
        APPLY TO ANY OBJECTS SUBJECT TO LESSOR'S CONTRIBUTION TO EXPENSES ON
        FITTING OUT UNDER SECTION 17, SUB-PARAGRAPH 1 OF THIS LEASE. The
        obligation to execute decorative repairs according to Section 10 remains
        unaffected.

3.      Additionally, Lessee shall indemnify for any loss suffered by Lessor due
        to delayed return of the leased rooms.

4.      On Lessor's demand to remove the installations/alterations Lessee is
        obligated to restore the original condition, or the condition originally
        agreed, at its own expense, including each and every necessary secondary
        work.

                                     SECTION
                                   SUBLEASING

1.      Lessor is entitled to sublease or sublet the Leased Property subject to
        Lessor's prior written consent, but only

a)      for the same or similar purposes of use, for which the rooms are leased
        to Lessee and

b)      to a sublessee convenient to Lessor. Lessor may reject a sublessee
        only, if sublessee's person, branch of business or company gives
        substantial cause for such a rejection.

2.      Subleasing for the purpose of a changed use of the Leased Property
        Acquires Lessor's special written consent.

                                    SECTION 7
                     AMOUNT OF RENT AND INCIDENTAL EXPENSES

1.      The monthly rent for the leased areas shown in Section I amounts to

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 a) approx l,122.l2 m(2)            x DM   27.50 = DM 30,858,30
 b) approx l12.09 m(2)              x DM   20.00 = DM 2,241.80 (offices)
 c) approx l24.76 m(2)              x DM   12.00 = DM 1,497.12 (storage area 1)
 d) 6 parking spaces undergr. c. p. x DM  110.00 = DM 660.00
 e) 2 PARKING SPACES OUTSIDE        x DM   60.00 = DM 120/00
    ---------------------------------------------------------------------------

        total                                    = DM 35,377.22

LESSOR ALLOWS LESSEE THE USE OF THE LEASED PROPERTY FREE OF RENT FOR THE FIRST
THREE MONTHS OF LEASE AFTER HANDING OVER (POSSIBLY EARLIER REGARDING PARTIAL
AREAS), NOT LONGER, HOWEVER, THAN UNTIL MARCH 31ST, 1998. THE ADVANCE PAYMENT
FOR THE OPERATING EXPENSES IS DUE ON HANDING OVER OF THE RESPECTIVE LEASED AREA
(INCLUDING PARTIAL AREAS).

2.       The incidental expenses listed in the following are not covered by the
         rent payment:
              real estate and building insurance
              real property tax
              cost of water and waste water
              cleaning expenses streets, paths and squares
              upkeep of decorative elements and of general green areas including
                  purchasing costs of new plants
              costs of fire alarm and extinguishing systems, safety contrivances
                  of all kinds (if available)
              costs of caretaker or in-house technician costs of house cleaning
              costs of the heating system including consumption
              general current, lamps
              metering and accounting expenses of consumption elevator costs
              refuse collection - unless separate agreement cost of ventilation,
                 air conditioning equipment
              wide band supply
              upkeep and repair of interior and exterior general areas, except
                 for roof, outer facades and
                 load-bearing elements
                 house management

         Lessee shall bear these costs according to actual consumption or to the
         corresponding expenses incurred.

         Industrial waste, e.g. office paper, overstepping the mark, is to be
         removed by Lessee.


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         To the extent that costs are apportioned, Lessee shall be treated as
         equivalent to the other lessees (applying the same basis for
         allocation), irrespective of the operating expenses.

         A monthly advance payment of DM 5.50 per M(2) shall be collected for
         the above mentioned incidental expenses for the offices and the
         supplementary area. This advance payment is to be effected together
         with the rent payment. In the case of a change of these incidental
         expenses or if new real property liens arise, Lessor shall be entitled
         to reassess the advance payments.

         Settlement of accounts with respect to the advance payments will be
         effected once a year. If the settlement of accounts shows an
         overpayment a corresponding credit note in favor of Lessee will be
         issued. If the costs to be settled exceed the advance payments, Lessor
         shall claim a corresponding payment. Provided economically justifiable
         corresponding supply meters are to be installed for the determination
         of consumption. Unless a direct determination of such costs is
         possible, Lessee shall be charged with these costs in proportion of its
         leased area to the overall leased area of the Property. In the case of
         a breakdown of the metering devices or if such devices do not work
         properly, Lessor is entitled to allocate costs by way of assessment.

         The accounting documents shall he available for inspection according to
         Lessor's provisions for one month after dispatch of the settlement of
         accounts to the lessees.

3.       Lessee shall pay a monthly flat charge of 1% of the net rent agreed
         under Section 7, sub-paragraph 1, for the proportionate administrative
         expenses.

4.       In addition to the rent, any value added tax to the extent assessed and
         due shall be owed by Lessee. This also applies to incidental and
         administrative expenses listed above.

                                    SECTION 8
                     PAYMENT OF RENT AND INCIDENTAL EXPENSES

1.       The rent and the advance payment for incidental and administrative
         expenses are to be paid to Lessor or to a person or institution
         authorized by Lessor for acceptance monthly in advance not later than
         on the third working day of the respective month. For the first time,
         these payments are to be effected for the period from the day of
         handing over the Leased Property.

2.       On delay in payment, Lessor is entitled to charge default interest of
         4% above the respective discount rate of the Deutsche Bundesbank as
         well as dunning costs to the extent of DM 5.00 PER REMINDER. The
         assertion of further damages caused by delay remains unaffected.

3.       In the case of partial payments on the part of Lessee, Lessor is
         entitled to offset according to Section 366 II German Civil Code BGB,
         irrespective of any statements by Lessee.

4.       Lessor shall not pay any interests on advance payments for incidental
         expenses.

5.       THE RETENTION OF PAYMENTS TO BE EFFECTED BY THE PARTIES UNDER THIS
         CONTRACT AND THEIR OFFSET AGAINST ANY CLAIMS IS EXCLUDED, UNLESS
         ACKNOWLEDGED OR RECOGNIZED BY DECLARATORY JUDGMENT BY THE OTHER PARTY.
         LESSEE'S RIGHT TO CLAIM REDUCTION OF RENT REMAINS UNAFFECTED.


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         Lessor's banking connection

         Bayerische Landesbank
         Account no. 58 301
         bank identification no BLZ 700 500 00

                                    SECTION 9
                        RENT ADJUSTMENT / VALUE GUARANTY

1.       The tent agreed under Section 6, sub-paragraph 1 is to be considered as
         fixed until December 31st, 1998. After that date, it shall be increased
         or reduced in percentages for the following year according to
         cost-of-living index of an employee's family of four with an average
         income of the sole breadwinner, as published by the Statistisches
         Landesamt NRW (Land Statistical Office of North Rhine-Westphalia) on
         the basis of 1991 = 100 points, with 75 % corresponding to the increase
         or decrease of the index.

         A FIRST ADJUSTMENT OF RENT WILL BE EFFECTED ON JANUARY 1ST, 1999. THE
         CHANGE OF INDEX FROM DECEMBER 1997 (BASE INDEX) TO DECEMBER 1998 IS
         AUTHORITATIVE FOR THIS ADJUSTMENT. SUBSEQUENTLY, THE RENT ADJUSTMENT
         SHALL BE EFFECTED ON JANUARY 1ST OF EACH YEAR OF LEASE, ALSO ACCORDING
         TO THE RESPECTIVE CHANGE OF INDICES FROM DECEMBER OF THE PREVIOUS YEAR
         IN RELATION TO DECEMBER OF THE YEAR BEFORE.

         In the following years of Lease, a corresponding adjustment of rent
         shall be effected on January 1st, respectively.

2.       If in future this adjustment becomes legally impossible for any reason
         whatsoever, e.g. because this index is no longer officially determined
         or published or if the connection hereto becomes legally impossible for
         any reason whatsoever, the contracting parties are bound to come to an
         agreement on a reasonable adjustment of rent which is permitted by
         statute and the content of which is economically as similar as possible
         to the value clause agreed hereunder.

3.       The contracting parties are aware of the fact that the legal effect of
         the above value clause is dependent on the approval by the Land central
         bank. Lessor will endeavor immediately to obtain such approval. The
         legal effect of the other provisions of this contract remain
         unaffected, as long as the approval by the Land central bank has not
         been obtained or if it is denied. In that ease, the contracting parties
         are bound to work on a permissible wording in order to achieve a
         corresponding rent restriction to the development of the cost of
         living.

                                    SECTION 10
                             MAINTENANCE AND REPAIR

1.       On beginning of contract, the leased rooms are handed over to Lessee in
         a new, perfect condition. Prior to move, any possible defects are
         recorded in a handing over protocol. During the rental period, the
         leased rooms are to be kept in a proper unobjectionable condition and
         are to be treated with care.

2.       During the rental period, Lessee shall additionally be responsible for
         all repairs within the Leased Property caused by its own fault or by
         inexpert handling (repair, maintenance) and for all the interior
         decorative repairs. Lessee shall perform expert interior decorative
         repairs at its own

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         expense at reasonable intervals, not later than every 3 years.

3.       Lessee shall remove immediately any damages, he is responsible for. If
         Lessee fails to comply with this provision within a reasonable period
         of time, Lessor may have the necessary works executed at Lessee's
         expense.

4.       In the case of damages causing any imminent dangers or in the case of
         unknown abode of Lessee, a written caution or the fixing of time limit
         is not required. In such cases, Lessor is entitled to execute damage
         removal at Lessee's expense.

                                    SECTION 11
                              INSURANCE, LIABILITY

1.       Insurance of Lessee's fittings and of stored assets against fire,
         water, burglary and housebreaking or other damages is within Lessee's
         responsibility.

2.       In particular, Lessee is liable for the following damages to the Leased
         Property:

a)       any damages to the fittings and other objects brought in by Lessee,
         caused by fire or tap water, including the risks of sewage water and
         inappropriate penetration of sprinkler water;

b)       any personal injury and damage to property to an extent customary in
         Lessee's line of business

c)       broken glass

d)       any damages resulting from burglary and housebreaking.

3.       Lessee shall effect insurances covering the risks mentioned under a-d.

         Lessor may demand presentation of corresponding insurance policies in
         regular intervals, including a written declaration by the insurance
         company confirming that a corresponding examination has not shown a
         case of underinsurance.

4.       Lessor assumes no liability whatsoever for any possible damages to
         fittings, unless the damage has been NEGLIGENTLY caused by Lessor or by
         its vicarious agents. LESSOR, HOWEVER, SHALL BE LIABLE FOR ANY DEFECTS,
         LESSEE IS EXPRESSLY NOT LIABLE FOR ACCORDING TO THE FOLLOWING.

5.       In the case of subleasing, Lessee shall indemnify Lessor against any
         claims to such an extent as such claims against Lessor are excluded for
         Lessee itself according to the terms of this contract. This also
         applies to non-contractual foundations for claims.

6.       LESSEE IS LIABLE FOR ANY DAMAGES NEGLIGENTLY CAUSED BY ITS FAILURE TO
         EXERCISE PROPER CARE, INCLUDING WITHOUT LIMITATION, IN PARTICULAR,
         INEXPERT HANDLING OF SUPPLY PIPES OR DRAINS, TOILETS AND HEATING PLANTS
         OR OF ELECTRICAL EQUIPMENT WITHIN THE LEASED ROOMS, AND FAILURE TO
         PROTECT THEM SUFFICIENTLY FROM FROST OR OTHER INFLUENCES. AT ALL
         EVENTS, OCCLUSIONS OF PIPES ARE TO BE REMOVED BY LESSEE UP TO THE MAIN
         PIPE AT ITS OWN EXPENSE.


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7.       IN THE SAME WAY, LESSEE IS LIABLE FOR ANY DAMAGES NEGLIGENTLY CAUSED TO
         THE PROPERTY BY ITS EMPLOYEES OR SUBLESSEES. IF SUCH DAMAGE IS CAUSED
         BY LESSEE'S OR SUBLESSEE'S VISITORS OR SUPPLIERS, LESSEE IS LIABLE
         ONLY, IF IT FAILS TO INFORM LESSOR ABOUT THE FULL NAME AND ADDRESS OF
         THE VISITOR OR SUPPLIER (SPECIFIC EXECUTING PERSON).

         LESSEE SHALL MAINTAIN ANY PIPES AND PLANTS RELATING TO ELECTRICITY, GAS
         AND SANITATION, LOCKS, BLINDS, AND SIMILAR EQUIPMENT IN A SERVICEABLE
         CONDITION.

         LESSEE IS FURTHER LIABLE FOR ANY DAMAGE CAUSED BY INEXPERT HANDLING OR
         WATER, LIGHT AND POWER MAINS, AND FOR ANY DAMAGE TO TOILETS, SANITATION
         OR HEATING PLANT AS WELL AS VENTILATION, SMOKE ALARMS AND ACOUSTIC
         EQUIPMENT (IF AVAILABLE) CAUSED BY LEAVING DOORS OPEN, BY STRUCTURAL
         MEASURE TAKEN BY LESSEE, BY ADVERTISING EQUIPMENT INSTALLED BY LESSEE
         OR BY FAILURE TO COMPLY WITH THE OTHER OBLIGATIONS ASSUMED BY LESSEE.

         Lessee is liable to Lessor for any damages to buildings, doors, gates,
         elevators, parking lots, traffic ways etc, caused by delivery traffic
         and exceeding customary wear and tear.

8.       AT ALL EVENTS, LESSOR SHALL REPLACE AT ITS OWN EXPENSE ANY DAMAGED
         GLASS PANES AND MIRRORS IF NECESSARY, LESSOR SHALL EFFECT A GLASS
         INSURANCE. NOT CLOSING TOILETS AND SINKS, CAUSING WATER TO FLOW
         CONTINUOUSLY THROUGH LEAKY VALVES THUS RESULTING IN CONSIDERABLE WATER
         CONSUMPTION, ARE IMMEDIATELY TO BE REPORTED TO LESSOR. DELAYED REPORTS
         MAY RESULT IN DAMAGE CLAIMS. ON REQUEST, ANY POSSIBLE CLAIMS AGAINST
         THIRD PARTIES AT FAULT ARE ASSIGNED TO LESSOR BY LESSEE.

9.       Lessee is responsible for not exceeding the indicated carrying capacity
         of the bearing plate.

10.      Lessee shall immediately remove any damages it is responsible for
         according to the above provisions at its own expense. On Lessee's
         failure to do so despite written caution and fixing of an appropriate
         time limit by Lessor, Lessor may have the corresponding work executed
         at Lessee's expense. In the case of damages causing any imminent
         dangers or in the case or unknown abode of Lessee, a written caution of
         fixing of time line is not required.

11.      Lessor shall arrange for the examination of plants jointly used by
         several leases or belonging to the commonly used facilities. Lessor is
         entitled to sign the appropriate fully comprehensive maintenance
         agreements. Costs shall be apportioned to the lessees. The required
         examination of plants exclusively used by Lessee or installed by Lessee
         is to be arranged for by Lessee at its own expense. Lessee is obligated
         to observe and comply with each and every statutory or public law
         provision with respect to its place of business.

12.      Plats and components left for Lessee's sole use are to be maintained,
         attended to and kept up in such a way, that they are returned in a
         serviceable condition after termination of contract.

                                    SECTION 8
                         PREMATURE TERMINATION OF LEASE

1.       Lessor generally agrees to give its consent to annulment of contract in
         the case that Lessee demands early termination of contract for
         substantial reasons, provided that

<PAGE>

         Lessee presents an equivalent and solvent new lessee with whom a
         contract of lease is entered into, in which the new lessee succeeds
         to each and every right and obligation under this contract.

         The new Lessee's use of the Leased Property for other than the previous
         purposes is subject to Lessor's consent. Lessor may deny such consent,
         if any non-competitive clauses agreed by Lessor or justified interests
         of other lessees or the mixture of branches are adverse to such use.

2.       Additionally, a precondition for Lessor's consent is that Lessee or the
         new lessee binds itself by contract with Lessor to bear all the
         expenses involved in the change of lessee (including commercial agency
         charges) and finally that Lessee assumes the absolute guaranty for the
         performance of the financial obligations of the new lessee against
         Lessor for the time up to the first possible date of termination.

                                    SECTION 13
               STRUCTURAL ALTERATIONS ARID INSTALLATIONS BY LESSEE

1.       Prior to and during the rental period, any structural alterations
         within and outside the leased rooms are subject to Lessor's written
         consent. Lessee is entitled to install advertising writings or signs in
         areas of the Leased Property earmarked by Lessor. In order to achieve a
         uniform design of the overall property, however, Lessee is obligated to
         have such exterior advertising approved by Lessor in advance. Any
         possible official permits are required to be obtained in advance by
         Lessee at its own expense. Even if Lessor grants it consent to
         structural alterations and installations, Lessee is obligated to remove
         such installations and to restore the original condition on termination
         of Lease.

         Subject to Lessor's consent, Lessee may leave any objects affixed to
         the building to Lessor free of charge. Lessee may also have its company
         name installed in the entrance area of the building at its own expense,
         uniform with the other users of the building and in accordance with
         Lessor (a uniform sign board is planned for all the lessees, divided up
         into individual signs).

         Lessee is entitled to equip the rooms at its own expense with
         additional installations and special facilities which are useful and
         necessary for the performance of its business.

         As soon as possible after completion of the contract, Lessee shall draw
         up a catalogue with such items and submit it to Lessor for approval.
         Planning, installation or delivery of Lessee's special facilities is
         within Lessee's responsibility. In agreement with Lessor's architect,
         however, it may make use of his expert assistance against payment of a
         reasonable remuneration,

2.       Regarding the electric installations required and ordered by Lessee,
         which arc subject to VDE/TUV, Lessee is obligated to entrust an expert
         company. Upon Lessor's demand, Lessee shall present the electricity
         plans.

                                    SECTION 14
                   REPAIR AND STRUCTURAL ALTERATIONS BY LESSOR

1.       Even without Lessee's consent, Lessor may perform any repairs and
         structural alterations becoming necessary for the maintenance of the
         building or of the Leased Property, for averting

<PAGE>

         imminent dangers, for the removal of damages or because of other
         lessees moving in/out.

         This shall also apply to works which are not necessary but useful, as
         for instance modernization of the building and of the Leased Property.
         DURING THE FIRST TEN YEARS OF LEASE, A MODERNIZATION OF LESSEE'S ROOMS
         IS SUBJECT TO LESSEE'S PRIOR CONSENT. Lessee shall maintain accessible
         the rooms concerned. Lessee must not hinder or delay the execution of
         the works.

2        Provided Lessee is bound to tolerate the works, it is not entitled to
         rent reduction nor to exercise a right of retention. Lessor, however,
         is obligated to have such works executed outside Lessee's usual
         business hours, if possible, in order to avoid a substantial
         interference with Lessee's business operation.

                                    SECTION 15
                      JURISDICTION AND PLACE OF PERFORMANCE

1.       Place of jurisdiction and place of performance is Dusseldorf.

                                    SECTION 16
                                SECURITY FOR RENT

1.       Lessee shall provide a guaranty to the extent of SIX NET MONTHLY RENTS
         to provide security for its obligations under this contract. This
         guaranty may be effected in the form of a bank guaranty issued for an
         unlimited period of time. On termination of Lease, the security is
         returned to the full extent, provided this contract of Lease is
         perfectly fulfilled and all other obligations in connection with this
         Lease are complied with. Otherwise the security provided shall be set
         off against Lessor's claims.

         Lessor may demand that the suretyship is increased corresponding to a
         rent increase as per Section 8 of this contract. Accordingly, the
         security is to be increased on I4essor's first demand in such a way,
         that it always matches SIX current net monthly rent payments.

     2.  If the security or an appropriate guaranty is not received by Lessor
         within 14 days after handing over of contract, Lessor is entitled to
         withdraw from contract after another written caution of 14 days.

                                    SECTION 17
                               SPECIAL CONDITIONS

1.       LESSEE IS GRANTED AN ADDITIONAL CONTRIBUTION TO EXPENSES ON FITTING OUT
         IN THE GROSS AMOUNT OF DM 350,000.00, IN ADDITION TO THE CONVENTIONAL
         DESIGN.

         THIS CONTRIBUTION MAY BE USED FOR FALSE FLOOR, AIR CONDITIONING IN
         VARIOUS AREAS, ADDITIONAL STEEL DOORS AND FOR ADDITIONAL LAMPS AND
         OTHER SPECIAL REQUIREMENTS, WHICH ARE NOT INCLUDED IN THE STANDARD
         BUILDING SPECIFICATIONS.

2.       Lessor assumes the obligation of cleaning the pavement including snow
         removal and gritting in icy weather of the pavements and pedestrian
         areas in front of the building, complying with the municipality's
         provisions. The corresponding expenses will be apportioned to the
         lessees in accordance with Section 6, sub-paragraph 2.

<PAGE>

3.       Lessee agrees furthermore to clean windows and window frames regularly.
         This also applies to sun protection facilities. If cleaning contractors
         are entrusted with attending to the overall property, Lessee may join
         such an agreement provided it bears the proportionate expenses.

4        The house regulations attached from part of this Lease and shall be
         signed by the two parties as well. The legal provisions shall apply
         supplementary to these terms of contract.

5.       Annulment, amendments and supplements to this contract must be made in
         writing. Any verbal agreements, in particular on cancellation of the
         written form, are ineffective. EACH PARTY IS ENTITLED TO AFFIX ANY
         AGREEMENTS ON AMENDMENTS OR SUPPLEMENTS REGARDING THIS LEASE TO THIS
         DEED.

6.       If any provisions of this contract prove to be or become legally
         ineffective, the validity of the o other provisions of this lease shall
         remain unaffected. The contracting parties, however, agree to ensure
         that the ineffective provisions are replaced by other, economically
         equivalent, effective provisions, if possible.

7.       The following appendices form part of this contract:

a)       BUILDING SPECIFICATIONS DD. OCTOBER 23RD, 1997

b)       GROUND PLANS OF OFFICE AND STORAGE AREA

c)       House regulations

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Dusseldorf                                       Frankfurt, October 31st, 1997

---------------------------                      ---------------------------
Lessor                                           Lessee




<PAGE>



  Appendix to the Lease

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

  HOUSE REGULATIONS

1.       Lessee shall handle the leased areas and common rooms with care and
         instruct its employees accordingly. This applies, in particular, to the
         interior of the elevators, to the entrance area, and to the handling of
         mail boxes, the bell system, and of the windows and facilities for the
         protection against the sun.

2.       The building is opened by the janitor at a time to be agreed with the
         majority of lessees, at 7:00 o'clock in the morning closed at 18:30 in
         the evening. Lessee or the employee opening the entrance facilities
         earlier in the morning or later in the evening by means of a key, is
         obligated to relock these doors.

3.       Within its area of lease, Lessee shall provide a sufficient number of
         ashtrays, in order to avoid burn holes in the carpets. In the general
         area it has to be taken care that the ashtrays provided are used.

4.       Plantings which are only accessible through Lessee's leased area, are
         to be attended to by Lessee, i.e. regular watering, at least once a
         week.

5.       Any transports of furniture or other, which may require a locking of
         the elevator, are necessarily to be agreed with the house management in
         advance and may only be executed in the presence of the competent
         janitor.

6.       The stairwell areas, entrance facilities, basement and outer areas
         including glass parts are jointly attended to. The respective expenses
         are apportioned together with the incidental expenses to the individual
         lessees. Special outer entries (exclusively used by Lessee) are to be
         maintained and kept free from Snow by Lessee.

7.       The usual refuse is collected in a garbage skip and disposed of by the
         fleet of the municipality of Duesseldorf. Exceptional refuse as for
         instance larger amounts of paper, are to be disposed of by Lessee
         itself. If necessary, Lessee shall obtain a paper pressing plant. If
         several lessees intend to use such a plant together, this may be
         arranged for by the house management.

Dusseldorf                                    Frankfurt, October 31st, 1997

---------------------------                   -----------------------------
         Lessor                                            Lessee


<PAGE>


  Appendix 1 to the Lease

-------------------------------------------------------------------------------
BUILDING SPECIFICATION AS TO DESIGN

GENERAL                  On the premises Dusseldorf-Heerdt,
                         Prinzewnallee/Hansaallee, several office buildings are
                         constructed, one of them designed as multi-story office
                         building. This refers to the 1st and 2nd phase of
                         construction of an administration center at the corner
                         Prinzewnallee/Hansaallee.

                         Parking lots and a part of the required technical rooms
                         are planned to be housed in the basements.

                         In general, an up-to-date and well-appointed design of
                         unobjectionable workmanship corresponding to the state
                         of the art, to the DIN standards and to VOB (contract
                         procedure for building works) shall be realized,
                         completely serviceable, and in compliance with all the
                         regulations.

FOUNDATION SOIL          Gravel, sand, pressure according to ground certificate

LOAD CAPACITIES          On all office floors, a working load of 350 kg/m(2)
                         including allowance for partition walls is planned,
                         on the ground floor 500 kg/m(2)

PEDESTALS                Reinforced concrete according to static requirements.

TYPE OF CONSTRUCTION     Reinforced concrete framework construction in large
                         grid of 7.50/7.50 m,, made of site-mixed concrete or
                         partly site-mixed concrete. The framework of the
                         building is designed to minimize the number of bearers
                         reducing the rooms.

                         A grid of 1.50 m is planned for the facade so that a
                         division into individual offices of different sizes
                         and connections to partition walls is possible in
                         this grid. Axial measure of individual rooms is 3.00
                         m, of two-man offices 4.50 m. Open-plan and functional
                         rooms are possible, but will require the ventilating
                         system to be complemented or the installation of an
                         air conditioning plant.

                         Parapets and lintel aprons of solid concrete on the
                         outside assembly units and heat insulation of  10 cm

                         Window units as pivot hung windows in high-quality
                         aluminum/timber work construction (outside aluminum,
                         inside timberwork, sides facing the street equipped
                         with sound-insulating glazing.

                         All the widows can be opened for cleaning and airing.
                         The windows are thermically separated and equipped
                         with special insulating glass


<PAGE>


                         The semicircular building is cased by a structural
                         glazing facade of high-quality dark glass.

                         The facade shall be equipped with top-hung sash
                         windows for opening. Parapets consist of single-layer
                         mirror glass as cold facade with high-quality
                         insulation.

                         The window systems consist of insulating glass with
                         shading on the outside (gathering-up shutters for
                         shading, to be operated individually.) and a parapet
                         base with eased heating units or convectors installed
                         behind.

HEIGHT BETWEEN FLOORS

                         1st basement                 3.52 m
                         ground floor                 3.60 m /2.75 m clearance
                         1st to 5th/6th upper floor   3.60 m / 2.75 m clearance

ROOFS                    All the roofs, except for ceiling of the underground
                         car park are constructed as roofs without vapor
                         barrier insulation with repeated waterproof
                         sheltings, heat insulation and pepple covering. The
                         connections are fixed with connecting two-piece
                         aluminum profiles and sealed.

CEILINGS                 Ceilings of solid reinforced concrete on all floors.
                         The individual office floors shall be equipped with a
                         suspended aluminum sheet grid ceiling consisting of
                         perforated aluminum sheet panels. Elevator anterooms
                         and the entrance area are designed with a suspended
                         gypsum plaster board ceiling with sound protection
                         mats inserted.

FLOORS                   On the ground floor floating floor with heat
                         insulation according to DIN standards. On the upper
                         floors wash floor with an additional built-in
                         multiple duct in the floor along the windows for
                         future requirements by lessee. All the rooms shall be
                         equipped with an upper floor covering of
                         high-quality, roller chair resistant, antistatic
                         carpeted floor (supposed price DM 36.00/m(2)).

                         The semicircular building shall be equipped with a
                         false floor; 60 mm thick (total construction height:
                         110 mm).

                         All the sanitation rooms and toilets shall be
                         equipped with wall and floor tiles with decorative
                         coloring. The wall tiles are laid from floor to
                         ceiling. The kitchens shall be equipped with a
                         laminate floor covering.

WALLS                    Outer walls of the basements built with concrete
                         according to static requirements. On the outside
                         insulated from moisture, Sound insulation of not less
                         than 27 dBA.

                         Room partition walls are designed as high-quality,
                         flexible partition wall system with plastic-laminated
                         surface (for each m(2) of leased area, 0.5 m(2) of
                         wall are supplied), with edges and door frames
                         rounded, and with painted solid wooden doors.

<PAGE>

                         Lessor provides 0.5 m(2) of office partition wails
                         for each 1 m(2) of leased office space. If this
                         amount exceeds lessee's requirements, no credit note
                         can be issued, as a following lessee may assert its
                         claim to a more comprehensive equipment.

                         The entrance halls will convey a prestigious
                         impression. Glass cloth and natural stone coverings
                         will be used as wall covering.

                         Non load-bearing walls of the basement are
                         constructed as fair-faced brickwork and painted with
                         binder (ceilings as well).

                         Stairwell walls and pillars on the individual floors
                         shall also be equipped with fiber glass wallpaper and
                         painted. This also applies to the inner side of the
                         parapets.

FACADE                   The facade consists of concrete assembly units,
                         coated white and special steel cord shall serve as
                         railing. The gable sides of the building are covered
                         with glassed granite plates.

DOORS                    The entrance doors to the floors are provided in
                         glass with door handles made of special steel.
                         Construction according to official conditions. The
                         rooms' internal doors are laminated with white
                         plastic and will have a steel frame. The other doors
                         according to official provision

FITTING                  Built-in cupboards, furniture and curtains are not
                         part of the fitting provided.

DOMESTIC                 TECHNIQUE All the installation systems are to be
                         designed to enable a change of rise of the offices
                         without requiring major changes to the basic
                         installation

ELECTRIC INSTALLATION    Supply:  feed line 4 x 16 mm(2) separately for each
                         lessee.

                         DISTRIBUTION: (within the leased area) each lessee
                         obtains its own subdistribution with a connected load
                         of 30 kVA for the electric power supply of lighting
                         and current outlets in the window sill duct or false
                         floor (circular building).

                         A triple window sill duct run (170 mm steel sheet)
                         will be installed under the windows on the office
                         floors. -duct gait 1 and 2 (with front cover of
                         plastic) to provide space for current wall outlets
                         and connector boxes for telephone and EDP. -duct part
                         3 (with front cover of steel sheet) for the
                         separation of data cables In the circular building)
                         the installation is laid in the false floor.

                         Lessor installs one double current wall outlet for
                         each double window. It is for Lessee to provide
                         connector boxes for telephone and EDP.

                         SWITCHING: Each individual office is equipped with a
                         series switch with a current wall outlet for
                         cleaning purposes.


<PAGE>

                         BELL AND COMMUNICATOR SYSTEM: Each lessee obtains one
                         station (entrance/reception) and a bell key button at
                         the entrance of the building, and at the entrance of
                         the leased area) respectively.

                         TELEPHONE: Within the leased area (near the current
                         distribution), a vacancy is provided for the
                         installation of a telephone splitter. Cabling (from
                         main splitter to lessee's splitter) and the number of
                         individual lines is within lessor's responsibility
                         and to be agreed with "Telecom". The space required
                         for cabling is provided in the form of lines and
                         shafts for risers. Ordering, expenses and the overall
                         installation involved in the operation of the
                         telephone system and providing the telephone system
                         is within lessee's responsibility as well.

                         EDP: Ordering expenses and overall installation with
                         respect to the operation of an EDP system is within
                         lessee's responsibility as well.

                         ANTENNA:  In the basement of each building, a
                         connection to cable TV is provided.

                         EQUIPOTENTIAL BONDING: In the individual leased
                         areas, near the sub-distribution, there is an
                         equipotential busbar with a NYAF cable of 25 mm. Any
                         expenses and ordering of an equipotential bonding
                         (unless part of domestic technique) and other
                         protective measures (e.g. against excess voltage) and
                         screens of whatever kind, including but not limited
                         to telephone and/or EDP system are generally to be
                         borne by lessee. A lightening protection system
                         exists.

                         STAIRWELL:  Continuous safety lighting.  Auxiliary
                         lamps are switched on additionally by means of key
                         buttons/ motion detectors. Illumination not less
                         than 100 lux.

FITTINGS                 Lessor provides 50% of the required large field lamps
                         of 2 x 36 watts and installation according to the
                         grid of the ceiling.

ELEVATORS                The semicircular building houses 4 panoramic
                         elevators located in glass towers. All the office
                         buildings are equipped with amply dimensioned
                         interior elevators. The floors within the elevators
                         arc designed in granite. The walls are sheathed with
                         special steel sheets or a minor wall. Halogen spot
                         lighting is fitted into the ceiling. Elevators are
                         equipped with a special steel railing.

                         At the facade of the tower building, two glazed
                         elevators run freely up and down. The cages are cased
                         with polished special steel sheets or sheathed with a
                         mirror.


<PAGE>

                         The floor is covered with granite. Position indicator
                         and control board are sheathed with a special steel
                         covering.

                         Cage doors;
                         Two-part, all-automatic sliding doors.

                         The cages are sheathed with special steel sheets.
                         Cage walls are glazed. Lighting by halogen spots,
                         installed even with the ceiling. The floor is covered
                         with granite Doors and portals are built in with
                         polished special steel sheets. The cages are equipped
                         with a special steel railing.

PORTALS AND ENTRANCES

                         Portals and entrances are constructed as windscreen
                         system, in part two-story, in aluminum flame
                         construction, interior doors of the entrance area as
                         glass-only facilities. The floors of the entrances
                         are to be equipped with a designed granite floor
                         covering with integrated doormat.

STAIRWELLS               Stairwells are designed as stairwells open to the
                         elevator anterooms, allowing an easy,
                         organizationally important connection between the
                         floors

                         Railings are built as architecturally designed
                         special steel railings.

                         The internal stairs are covered with high-quality
                         granite tiles. The escape stairs are covered with
                         high-quality Quarella tiles and steps.

HEATING                  Heat generation is effected by an all-automatic
                         heating installation with gas-operated
                         low-temperature heating furnaces. The heating system
                         is complemented by a weather dependent flow
                         temperature controller, Staefa with Wilo-pumps. A
                         heat reduction in the night and a weekend program are
                         planned. At each window center line of 1.50 m, modern
                         convectors, equipped with thermostatic valves, are
                         planned to serve as heating units. These heating
                         units dispose of a smooth and elegant front plate,
                         fitting; optically well into these window axis and
                         providing a flexible division of the rooms.

SANITATION               The cold water pipes are designed in copper. In the
                         room of the house connections, a filter is supposed
                         to keep away any penetrating impurities. Current
                         supply lines are laid to the washstands for warm
                         water supply of the lavatory basins. The installation
                         of a no-pressure hot-water apparatus is to be
                         provided by lessee if so required.

                         All the installations are planned in white color
                         Lavatory basins (56 cm), toilet with plastic lid and
                         built-in flushing box. Each washstand is equipped
                         with a mixing faucet with cam type closure, crystal
                         mirror and chromium-plated towel-rails. In each water
                         closet, a coat hook is planned. In the small kitchens
                         on each floor, kitchen supply is provided for. Here
                         again, a current feeding line is planned for a
                         hot-water apparatus.


<PAGE>

                         Drainage of the roof is effected by special roof
                         inlets and drain pipes leading into a well drain.
                         From there, through a pipe system in the ground, the
                         rain water trickles away. In the technical and
                         connection rooms, inlets are planned.

VENTILATION              All the rooms are mechanically ventilated. Change of
                         air: approx. triple. Additionally, the offices will
                         be equipped with heating units for static basic
                         heating. All the outgoing air gets out through air
                         evacuation valves, ducts and ventilating devices. In
                         the ventilating device, the residual heat of the
                         outgoing air is used by means of heat recovery. This
                         heat is delivered to the fresh air. Each ventilating
                         device disposes of a heater and a cooler, so that
                         according to the outdoor temperature warmed or cooled
                         air is insufflated through the air valves in the
                         intermediate ceiling.

COOLING                  An air cooling plant is provided, which guarantees
                         basic cooling (approx. 4 K below outdoor temperature)
                         corresponding to ventilation. Full cooling of the
                         offices can be retrofitted by lessee at lessee's
                         expense, requiring a comparably small effort. For the
                         purpose of such retrofitting or of EDP cooling,
                         cooling water systems are preinstalled on the office
                         floors. The cooling water system is lead up to the
                         individual floors as closed system including
                         recooling plant, pumps and pipe network. At the
                         transfer spot, a later connection of secondary
                         cooling plants is possible at any time.

GROUNDS                  Parks and gardens with a lot of large trees, numerous
                         bushes, lawns, fountains and works of art in the open
                         countryside, roofs are planted with plants.

    Amended; October 23rd, 1996


<PAGE>


    Appendix 2 to the Lease (Additional agreement), Prinzenpark with the company
    Star Telecommunications Deutschland GmbH

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

         Additionally, Lessor shall assume:

1.       False floor of the technical area on the ground floor Prinzenallee 7 at
         Lessee's choice.

2.       The large field lamps (2 x 36 watts) according to the regulations on
         work places (Arbeitsstatten-Richtlinien) are provided in full and
         installed by Lessor.

3.       On the ground floor to the right, a steel door (cased) is installed and
         a mobile ramp is provided.

4.       As Lessee wishes to bring in its own carpet with its own logo, Lessor
         shall credit DM 50.00 per m(2). This only refers to the commercial area
         on the ground floor (not exceeding 300 m(2).

5.       A distribution box for the electric installations is supplied and
         installed.

6.       Lessor guarantees Lessee a grounding of [less than or equal to] 1ohm.

7.       Lessor provides Lessee a current supply with 3 phases of 65 KW each,
         but only until Lessee is provided with an own transformer by the city's
         department of works (Stadtwerke).

8.       With respect to infrastructure suppliers, Lessor allows Lessee that the
         company ISIS or the Telcom are authorized to perform core drillings, in
         order to be able to insert supply lines. Lessee is obligated to assume
         the liability for any damages caused by such core drillings.