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                                                                    EXHIBIT 10.5

                                 LEASE AGREEMENT

         AGREEMENT entered into as of the first 1st) day of March, 1999, between
Cortelco Puerto Rico, Inc., hereinafter called the "Landlord", and Cortelco
Systems Puerto Rico, Inc., hereinafter called the "Tenant".

                                    PREAMBLE

         Landlord hereby leases to the Tenant and the Tenant hereby hires from
the Landlord certain building space consisting of approximately 19,915 square
feet, identified as the area shaded and marked "Premises" on the attached
Exhibit A (the "Premises") and which are part of the building identified in said
Exhibit A (the "Building"), including ingress and egress to the public roadways
as these are depicted on Exhibit A. The premises consist of approximately 12,275
square feet of showroom space and approximately 7,640 square feet of office and
administrative space, located at 1550 Ponce de Leon Avenue. The term of this
lease shall be for a period of five (5) years commencing on the first (1st) day
of March, 1999, hereinafter called "term commencement date" and expiring on the
thirty-first (31st) day of March, 2004.

         Provided Tenant is not in default hereunder, it shall have the option
to renew the term of this lease for two (2) consecutive periods of one (1) year
each, as further specified in Article XXIV hereof.

         Tenant shall pay to Landlord, without demand and without deduction,
abatement or set-off in advance on or before the 5th day of each month the sum
of $25,308.65 (the "base rent").

         Tenant shall have the right to use forty (40) parking spaces in any of
the employees parking lots, and twenty (20) parking spaces in the main building
patio to be assigned at Landlord's discretion.

         The parties covenant and agree as follows:

                           ARTICLE I PAYMENT OF RENT;
                                SECURITY DEPOSIT

         The Tenant shall pay the base rent with respect to the Premises and the
Parking, as specified above, and an additional rent as set forth in Article XVI
below, without any deduction or set-off whatsoever.

                                   ARTICLE II
                                     PURPOSE

         The Premises shall be used and occupied for any legal purpose relating
to Tenant's business.
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                                  ARTICLE III
                               ALTERATIONS; SIGNS

         The Tenant shall make no alterations, additions or improvements to the
Premises, nor erect any sign on the facade of the Building, without the prior
written consent of the Landlord. All such alterations, additions or improvements
made by or for the Tenant, shall, when made, be the property of the Landlord and
shall remain upon and be surrendered with the Premises as a part thereof at the
expiration or earlier termination of this lease, except that the Tenant shall
have the right to remove any alterations installed by Tenant and which can be
removed without damaging the Premises. Also, Landlord reserves the right to
require the Tenant to remove any such alterations, additions, improvements or
signs including, but without limitation, stairs, stair wells, floor coverings
and other fixtures installed by or at the request of the Tenant, by giving
notice of such election to the Tenant at any time prior to, or not later than
ten (10) days after the expiration or earlier termination of this lease, in
which event the Tenant, at the Tenant's sole cost and expense, shall remove the
items specified on or before such date of expiration or earlier termination of
the term of this lease or five (5) days after the giving of such notice,
whichever shall be the later, and shall promptly reimburse the Landlord for the
cost of restoration of the Premises and of repairing all damage done to the
Premises by such removal.

                                   ARTICLE IV
                                  TENANT'S CARE

         The Tenant shall take good care of the Premises and the fixtures
therein and at the expiration or earlier termination of this lease will
surrender the Premises and fixtures in as good condition as reasonable use will
permit, ordinary wear and tear excepted. All injury to the Premises, the
Building or the sanitary, electrical, air conditioning or other systems or
fixtures thereof caused by moving the property of the Tenant in or out of the
Building or resulting from the act or neglect of the Tenant or the employees,
servants, agents, licensees, visitors, assigns or undertenant of the Tenant,
shall be repaired promptly by and at the expense of the Tenant in a workmanlike
manner, and if the Tenant fails to do such work, the same may be done by the
Landlord, and the cost thereof shall be payable by the Tenant to the Landlord.

                                   ARTICLE V
                            ORDINANCES AND VIOLATIONS

         The Tenant, at the Tenant's expense, shall promptly execute, fulfill
and comply with all laws, rules, orders, ordinances, regulations and
requirements of any governmental authority claiming jurisdiction over the
Premises and all requirements of any Board of Fire Underwriters,


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or any similar body, to the extent the same or any of them affect the Tenant's
occupancy of the Premises, or the business conducted therein. ARTICLE VI
INSURANCE

         1. Tenant will procure and maintain and pay all premiums, fees and
charges for the purpose of procuring and maintaining continuously throughout the
term of this lease: (a) insurance on the Premises and the improvements thereon
against loss or damage by fire or other casualty with endorsements providing
what is commonly known as all risk fire and extended coverage, vandalism and
malicious mischief insurance, in an amount equal to the full replacement cost
thereof, with a deductible of no greater than $5,000; and

                  (b) general liability insurance with respect to the Premises
and the Parking with a combined single limit of not less than $2,000,000 for any
bodily injury or property damage, with a deductible of no greater than
$1,000.00, which insurance specified in (a) and (b) shall name Landlord as an
additional insured, with insurers satisfactory to Landlord and authorized to do
business in Puerto Rico.

         2. If, because of anything done, caused to be done, permitted or
omitted by the Tenant, the premium rate for any kind of insurance affecting the
Building shall be increased, the Tenant shall pay to the Landlord the additional
amount which the Landlord shall be thereby obligated to pay for such insurance,
and if the Landlord shall demand that the Tenant remedy the condition which
caused the increase in the insurance premium rate, the Tenant will remedy such
condition within five (5) days after such demand. The Tenant shall not do, or
cause to be done, or permit on the Premises anything deemed extra hazardous on
account of fire. The policies shall contain a clause that the insurer will not
cancel or change the insurance policies without first giving Landlord thirty
(30) days prior written notice.

                                  ARTICLE VII
                                    INDEMNITY

         The Tenant shall indemnify and save harmless the Landlord and the
agents, servants and employees of the Landlord against and from any and all
liability, fines, suits, claims, demands, expenses and actions of any kind or
nature arising by reason of injury to person or property occurring in the
Premises, the Building or the Parking (as the case may be) occasioned in whole
or in part by any act or omission on the part of the Tenant or an employee
(whether or not acting within the scope of employment), servant, agent,
licensee, visitor, assign or undertenant of the


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Tenant, or by any use or occupancy of the Premises or any breach, violation or
non-performance of any covenant in this lease on the part of the Tenant to be
observed or performed.

                                  ARTICLE VIII
                      RIGHT OF LANDLORD TO ENTER PREMISES

         The Landlord shall have the right to enter and to grant licenses to
others to enter the Premises at any time (a) to examine the Premises, (b) to
make repairs, replacements and improvements to the Premises or to the Building
or equipment thereof, including the right during the progress of any such work
to keep and store within the Premises all necessary materials, tools and
equipment (but nothing herein shall obligate the Landlord to make any repairs,
replacements or improvements other than as expressly set forth in this lease),
(c) for any purpose which the Landlord may deem necessary for the operation and
maintenance of the Building, or (d) to exhibit the Premises to prospective
purchasers or mortgagees (and during the last twelve (12) months of the term of
this lease, to prospective tenants), and no such entry shall render the Landlord
liable to any claim or cause of action for damages by reason thereof.

                                   ARTICLE IX
                       REPAIRS AND ALTERATIONS IN BUILDING

         The Landlord reserves the right to make such repairs, changes,
alterations, additions or improvements in or to any portion of the Building and
the fixtures and equipment thereof as it may deem necessary or desirable and,
for the purpose of making the same, to use the street entrances, halls, stairs
and elevators of the Building, provided that there be no unnecessary obstruction
of the Tenant's right of entry to the Premises, and the Tenant shall make no
claims for compensation or damages against the Landlord by reason of
inconvenience or annoyance arising therefrom.

                                    ARTICLE X
                                    UTILITIES

         The cost of all electricity (including that for air conditioning) and
all other utilities used by the Tenant in connection with its business on, or
occupancy of, the Premises from 8:00 AM to 5:00 PM Mondays through Fridays
(excluding legal holidays) (hereinafter "Regular Business Hours" ) shall be for
Landlord's account. The cost of all electricity (including that for air
conditioning) and all other utilities used by the Tenant in connection with its
business on, or occupancy of, the Premises outside Regular Business Hours shall
be for Tenant's account.



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                                   ARTICLE XI
                                   MAINTENANCE

         All maintenance and cleaning of the Premises, but excluding any
structural repairs to the Building, shall be furnished by and shall be for the
account of Tenant. Landlord shall make any required structural repairs necessary
to the Building at its own expense and Tenant agrees to notify Landlord promptly
of the need for any such repair. The term "structural repairs" shall not be
deemed to include water leaks or filtration affecting the walls or ceiling of
the Premises.

         Tenant and Landlord have examined and inspected the Premises and Tenant
hereby accepts the same in its present condition as of the date of the execution
hereof. Tenant acknowledges that neither Landlord nor Landlord's agents have
made any representation or warranty as to the suitability of the Premises for
the conduct of Tenant's business.

                                  ARTICLE XII
                            REAL ESTATE TAX INCREASE

         A. For the purpose of this Article the following terms shall have the
following meanings: "lease year" shall mean the twelve-month period commencing
on the term commencement date, and each twelve-month period thereafter; "real
estate taxes" shall mean any and all amounts which become due and payable during
a lease year in respect of taxes and assessments, special or otherwise, imposed
upon the Building and the lot upon which it is located; "tax base" shall mean
the real estate taxes due and payable for the fiscal year from July 1, 1997 to
June 30, 1998. If real estate taxes applicable to any lease year are greater
than the tax base, the Tenant shall pay as additional rent for such lease year a
sum equal to 2.7% of the amount by which real estate taxes are greater than the
tax base (hereinafter called "Tenant's tax payment"). In the event real estate
taxes applicable to a lease year are greater than the tax base, the Landlord may
give the Tenant, within ninety (90) days after the end of such lease year, or
within ninety (90) days after Landlord is notified of such tax, notice of
Tenant's tax payment for such lease year; provided, however, that if this lease
expires or is terminated during such lease year, Tenant's tax payment shall be
limited to an amount equal to Tenant's tax payment for such lease year
apportioned as of the date of such expiration or termination, and the Tenant
shall make payment of Tenant's tax payment or of the same as apportioned within
thirty (30) days after the giving of such notice, notwithstanding the fact that
this lease has expired or has been terminated prior to the time of the giving of
such notice. In the event the Landlord shall receive any refund as a result of a
reduction in real estate taxes for any lease year after the first lease year


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and a Tenant's tax payment for such lease year has been made by the Tenant, the
Landlord shall remit to the Tenant a sum equal to 2.7% of the refund received by
the Landlord for such lease year, after deducting from such refund all expenses
incurred by the Landlord in connection with obtaining the same, including
attorneys' fees. At Landlord's option, any additional rent attributable to an
increase in real estate taxes, or any decrease in rent due to a decrease in real
estate taxes, shall be payable by Tenant, or credited to Tenant, as the case may
be, on a monthly basis allocated evenly over the number of months in the lease
year, or balance of the lease year if such increase or decrease shall be
effective during the middle of a lease year.

         B. Tenant shall pay before delinquency all taxes, assessments, license
fees, and other charges which are levied against Tenant's alterations and
fixtures and which become payable during the term hereof. If any such
alterations or fixtures are assessed with Landlord's real property, Tenant shall
pay Landlord the taxes attributable to Tenant within thirty (30) days after
receipt of a written statement setting forth the applicable taxes.

         C. During the first and last years of the term hereof, all such taxes
and assessments which shall become payable during each of the calendar, fiscal,
tax or assessments years, as applicable, shall be ratably adjusted on a per diem
basis (based on the area that the Premises bears to the Building) between
Landlord and Tenant in accordance with the respective portions of such calendar,
fiscal, tax or assessment year.

                                  ARTICLE XIII
                                     DAMAGE

         The Landlord shall not be liable for damage to any proper or injury to
any person at any time in the Premises or Building by reason of any action of
the elements or arising from water, wind, rain, smoke, steam or electricity
which may leak into, or issue or flow from any part of the Building. The
Landlord shall not be responsible for any latent defect or change of conditions
in the Premises resulting in damage to the same or to the property or persons
therein unless due to the negligence of the Landlord, its agents, servants or
employees.

                                  ARTICLE XIV
            ASSIGNMENT AND SUBLETTING; LANDLORD'S OPTION TO TERMINATE

         1. Neither the Tenant nor the legal representative of the Tenant shall
assign, transfer or mortgage this lease or any interest therein or let or sublet
the Premises or any part thereof or permit the Premises or any part thereof to
be used by others without the prior written consent of the Landlord in each
instance, which consent may be withheld by Landlord at its sole discretion.


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In the event such consent be given, the same shall be deemed to relate solely to
the particular assignment, transfer, mortgage, sublease or permission referred
to in such consent. Consent shall not be given for a restaurant, or
manufacturing business.

         2. In lieu of granting its consent to a subleasing or assignment of
this lease, Landlord may, at any time when its consent is requested to an
assignment or subleasing, and within fifteen (15) days of the making of such
request, notify Tenant that this lease is terminated. Such termination shall
take place no less than thirty (30) and no more than sixty (60) days after the
date of such notice of termination by Landlord. In the event of such
termination, this lease shall upon the date so selected by Landlord terminate as
fully and completely as if the term hereof had expired.

                                   ARTICLE XV
                                  SUBORDINATION

         This lease is and shall be subject and subordinate to all mortgages and
ground leases which may now or hereafter affect the Building of which the
Premises form a part, and to all renewals, modifications, consolidations,
replacements and extensions thereof, and, although this subordination provision
shall be deemed for all purposes to be automatic and effective without any
further instrument on the part of the Tenant, the Tenant shall execute any
further instrument requested by the Landlord to confirm such subordination.

                                  ARTICLE XVI
                                 ADDITIONAL RENT

         All amounts over and above the base rent payable by the Tenant to the
Landlord under the terms of this lease shall be deemed additional rent hereunder
and shall be payable to the Landlord upon demand, unless provision is made
herein for payment of such amount on a specific date or within a specific time,
and, in default of payment, may, at the Landlord's option, be added to and
become a part of any subsequent installment of base rent falling due, and the
Landlord shall have all the rights and remedies in the event of non-payment
thereof as in the case of the base rent.

                                  ARTICLE XVII
          CONDITIONAL LIMITATIONS; DEFAULT PROVISIONS WAIVERS BY TENANT

1. If, during the term of this lease, the Tenant shall (a) apply for, or consent
in writing to, the appointment of a receiver, trustee or liquidator of the
Tenant or of all or substantially all of its assets, or (b) file a voluntary
petition in bankruptcy, or admit in writing its


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inability to pay its debts as they become due, or (c) make a general assignment
for the benefit of creditors, or (d) file a petition or an answer seeking
reorganization (other than a reorganization not involving the liabilities of the
Tenant) or arrangement with creditors, or take advantage of any insolvency law,
or (e) file an answer admitting the material allegations of a petition filed
against it in any bankruptcy, reorganization or insolvency proceeding, or, if an
order, judgment or decree shall be entered by any court of competent
jurisdiction on the application of a creditor adjudicating the Tenant a bankrupt
or insolvent, or approving a petition seeking reorganization of the Tenant
(other than a reorganization not involving the liabilities of the Tenant) or
appointment of a receiver, trustee or liquidator of the Tenant or, of all or
substantially all its assets, and such order, judgment or decree shall continue
uncontested and in effect for any period of sixty (60) consecutive days, the
Landlord may, at its option, give to the Tenant a notice of intention to end the
term of this lease at the expiration of five (5) days from the date of service
of such notice, and at the expiration of said five (5) days, the term of this
lease and all right, title and interest of the Tenant hereunder shall expire as
fully and completely as if that day were the date herein specifically fixed for
the expiration of the term, and the Tenant will then quit and surrender the
Property to the Landlord, but the Tenant shall remain liable as hereinafter
provided.

         2. If, during the term of this lease, (a) the Tenant shall default in
fulfilling any of the covenants of this lease (other than the covenants for the
payment of base rent and additional rent payable by the Tenant hereunder), or
(b) the Property shall be left vacant or unoccupied or be deserted for a period
of fifteen (15) days, or (c) this lease, without the prior written consent of
the Landlord shall be assigned or transferred in any manner or shall, by
operation of law, pass to or devolve upon any third party, the Landlord may give
to the Tenant notice of any such default or the happening of any event referred
to above and if at the expiration of thirty (30) days after the service of such
a notice the default or event upon which said notice was based shall continue to
exist, or in the case of a default which cannot with due diligence be cured
within a period of thirty (30) days, if the Tenant fails to proceed promptly
after the service of such notice and with all due diligence to cure the same and
thereafter to prosecute the curing of such default with all due diligence (it
being intended that in connection with a default not susceptible of being cured
with due diligence within thirty (30) days that the time of the Tenant within
which to cure the same shall be extended for such period as may be necessary to
complete the same with all due diligence), the Landlord may give to the Tenant a
notice of intention to end the term of this lease


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at the expiration of five (5) days from the date of the service of such second
notice, and at the expiration of said five (5) days the term of this lease and
all right, title and interest of the Tenant hereunder shall expire as fully and
completely as if that day were the date herein specifically fixed for the
expiration of the term, and the Tenant will then quit and surrender the Property
to the Landlord, but the Tenant shall remain liable as hereinafter provided.

         3. If the Tenant shall default in the payment of the base rent or
additional rent, or any part of the same and such default shall continue for
three (3) days after notice thereof by the Landlord or if this lease shall
terminate as in subdivision 1 or subdivision 2 of this Article provided, the
Landlord or the Landlords agents and servants may immediately or at any time
thereafter re-enter the Property and remove all persons and all or any property
therefrom, either by summary dispossess proceedings or by any suitable action or
proceeding at law, or otherwise, without being liable to indictment, prosecution
or damages therefor, and repossess and enjoy the Property with all additions,
alterations and improvements. Upon the termination of this lease by reason of
the happening of any of the events herein above described in subdivision 1 or
subdivision 2 of this Article, or in the event of the termination of this lease
by summary dispossess proceedings or under any provisions of law now or at any
time hereafter in force, by reason of, or based upon, or arising out of a
default under or breach of this lease on the part of the Tenant, or upon the
Landlord recovering possession of the Property in the manner or in any of the
circumstances hereinbefore mentioned, or in any other manner or circumstances
whatsoever, whether with or without legal proceedings, by reason of or based
upon or arising out of a default under or breach of this lease on the part of
the Tenant, the Landlord may, at its option, at any time, and from time to time,
relet the Property or any part or parts thereof for the account of the Tenant or
otherwise on such terms as the Landlord may elect, including the granting of
concessions, and receive and collect the rents therefor, applying the same first
to the payment of such expenses as the Landlord may have incurred in recovering
possession of the Property, including legal expenses, and for putting the same
into good order or condition or preparing or altering the same for re-rental,
and expenses, commissions and charges paid, assumed, or incurred by the Landlord
in and about the reletting of the Property, and then to the fulfillment of the
covenants of the Tenant hereunder. Any such reletting herein provided for may be
for the remainder of the term of this lease or for a longer or shorter period.
In any such case and whether or not the Property or any part thereof be relet,
the Tenant shall pay to the Landlord


                                       9

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the base rent and additional rent required to be paid by the Tenant up to the
time of such termination of this lease, or of such recovery of possession of the
Property by the Landlord, as the case may be, and thereafter the Tenant
covenants and agrees, if required by the Landlord, to pay to the Landlord until
the end of the term of this lease as originally demised the equivalent of the
amount of all the base rent and additional rent reserved herein, less the net
avails of reletting, if any, and the same shall be due and payable by the Tenant
to the Landlord on the several rent days above specified, that is to say, upon
each of such rent days the Tenant shall pay to the Landlord the amount of the
deficiency then existing. In any such circumstances the Landlord shall have the
election, in place and stead of holding the Tenant so liable, forthwith to
recover against the Tenant as damages for loss of the bargain and not as a
penalty, an aggregate sum which, at the time of such termination of this lease,
or of such recovery of possession of the Property by the Landlord, as the case
may be, represents the then present worth of the excess, if any, of the
aggregate of the base rent and additional rent that would have accrued for the
balance of the term over the aggregate rental value of the Property for the
balance of such term, unless any statute or rule of law governing the proceeding
in which such damages are to be proven shall limit the amount allowed on such
claim, in which case the Landlord shall be entitled as and for liquidated
damages by reason of such breach and termination of this lease, the maximum
amount which may be allowed by or under such statute or rule of law. In
computing the additional rent that would have accrued for the balance of the
term, the annual amount of the additional rent shall be deemed to be an amount
equal to the average of the annual amounts paid by the Tenant pursuant to
Article XVI hereof for the three years preceding the year in which such
termination occurs, or for such lesser period of time as this lease may have
been in effect prior to such termination. Nothing herein contained shall limit
or prejudice the Landlord's right to prove and obtain as liquidated damages
arising out of such breach or termination the maximum amount allowed by any
statute or rule of law which may govern the proceedings in which such damages
are to be proved whether or not such an amount be greater, equal to, or less
than the amount of the excess of the base rent and additional rent over the
rental value referred to above.

         4. The Tenant hereby expressly waives the service of notice of
intention to re-enter as provided for in any statute, or to institute legal
proceedings to that end, and also waives any and all rights of redemption in
case the Tenant shall be dispossessed by a judgment or by warrant of any court
judge.


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         The Tenant also waives any and all right to a trial by jury in any
matter arising out of or in connection with this lease or the right to assert a
counterclaim in any summary proceedings which may be instituted by the Landlord.
The terms "enter" and "re-enter", as used in this lease are not restricted to
their technical legal meaning. All of the covenants of the Tenant shall be
deemed and construed to be "conditions" as well as "covenants" as though the
words specifically expressing or importing covenants and conditions were used in
each separate instance. In the event any proceedings are brought against the
Tenant for non-payment of base rent or additional rent, or as a result of
termination of this lease, and whether or not such proceedings shall be
discontinued as a result of the Tenant paying such base rent or additional rent,
the Tenant will pay to the Landlord as a liquidated amount without necessity of
further liquidation or approval by the court, ten percent (10%) of the amount
claimed to be due from Tenant, if any, but in no ever/' less than $1,000.00, for
payment of Landlord's court costs, expenses, and attorneys' fees. Said amount
shall be due and payable upon the mere commencement by Landlord of said judicial
proceedings against Tenant.

                                 ARTICLE XVIII
                               LANDLORD'S REMEDIES

         In the event the Tenant shall default in the performance of any of the
terms, covenants or provisions herein contained, the Landlord may, at its sole
option, perform the same for the account of the Tenant and any amount paid or
expense incurred by the Landlord in the performance of the same shall be repaid
by the Tenant on demand. In the event of a breach or threatened breach by the
Tenant or any subtenant or other person holding claim or claiming under the
Tenant of any of the covenants, conditions or provisions hereof, the Landlord
shall have the right of injunction to restrain the same, and the right to invoke
any remedy allowed by law or in equity, as if specific remedies, indemnity or
reimbursement were not herein provided for. The rights and remedies given to the
Landlord in this lease are distinct, separate and cumulative, and no one of
them, whether or not exercised by the Landlord, shall be deemed to be a waiver,
or in exclusion, of any of the others.

                                  ARTICLE XIX
                             FIRE OR OTHER CASUALTY

         If the Premises shall be damaged by fire or other casualty, then Tenant
shall have the option to be exercised within sixty (60) days after such event,
to:

                  (a) Repair or restore the Premises; or


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                  (b) terminate this lease (provided the fire or casualty is not
attributable to Tenant's negligence, acts or omissions) by notice to Landlord,
which termination shall be deemed to be effective as of the date of the fire or
casualty. If Tenant terminates this Lease pursuant to this section, Tenant will
surrender possession of the Property to Landlord immediately, free and clear of
all liens, mortgages and encumbrances created by or through Tenant, and assign
to Landlord (or, if the same has already been received by Tenant, pay to
Landlord) all of its right, title and interest in all of the proceeds from
Tenant's insurance upon the Premises. If the Building be so damaged that the
Landlord shall decide to demolish and/or to reconstruct the Building, the
Landlord may terminate this lease by notifying the Tenant within a reasonable
time after such damage of the Landlord's election to terminate this lease, such
termination to be effective immediately if the term shall not have commenced or
on a date to be specified in such notice if during the term. In the event of the
giving of such notice during the term of this lease, the rent shall be
apportioned and paid up to the time of such fire or other casualty if the
Premises are damaged, or up to the specified date of termination if the Premises
are not damaged.

                                   ARTICLE XX
                                  CONDEMNATION

         If the Premises, or any part thereof, or any interest therein, be taken
by virtue of eminent domain or for any public or quasi-public use or purpose,
this lease and the estate hereby granted shall terminate as of the date of such
taking. If any part of the Building other than the Premises be so taken the
Landlord shall have the right to terminate this lease at the date of such taking
or within six (6) months thereafter by giving the Tenant thirty (30) days' prior
notice of the date of such termination. The Landlord shall be entitled to the
whole of any awards which may be paid or made in connection with any such
taking, and the Tenant shall not be entitled to any of such awards, hereby
expressly assigning to the Landlord any and all right, title and interest of the
Tenant now or hereafter arising in and to any of such awards.

                                  ARTICLE XXI
                                 QUIET ENJOYMENT

         The Tenant, on paying the rent and additional rent an keeping and
performing the conditions and covenants herein contained, shall and may
peaceably and quietly enjoy the Premises for the term aforesaid, subject,
however, to the terms of this lease and to the mortgages (if any) hereinbefore
mentioned.



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                                  ARTICLE XXII
                                     NOTICES

         Any statement or notice to, or demand on, the Tenant shall be deemed
given when mailed by certified or registered mail addressed to the Tenant at the
premises or when left upon the Premises, and any statement or notice to, or
demand on, the Landlord shall be deemed given when mailed by certified or
registered mail addressed to the Landlord at the following address if to Tenant:
1550 Ponce de Leon Ave, San Juan, Puerto Rico 00926, attention: Mr. Sergio
Moren, President, and if to Landlord, P.O. Box 363665, San Juan, Puerto Rico
00936-3665, attention: Mr. Francisco Sanchez, Vice President & Treasurer, or
such other address as the parties from time to time shall designate by written
notice.

                                 ARTICLE XXIII
                       NO REPRESENTATIONS - MODIFICATIONS

         The Tenant has hired the Premises after examination thereof and without
representation on the part of the Landlord. No representative or agent of the
Landlord is authorized to make representations in reference thereto or to vary
or modify this agreement in any way and no right of the Landlord can be waived
except in writing duly signed by the Landlord. The receipt by the Landlord of
base rent or any other sum payable by the Tenant with knowledge of the breach of
any covenant of this lease shall not be deemed a waiver of such breach and no
act or omission of the Landlord or its agent during the term of this lease shall
be deemed an acceptance of a surrender of the Premises and no agreement to
accept a surrender of the Premises shall be valid unless it be made in writing
and subscribed by the Landlord.

         This lease contains all the agreements and conditions made between the
parties hereto with respect to the Premises and this lease cannot be changed
orally, but any additions to or changes in this lease must be in writing signed
by the party to be charged.

                                  ARTICLE XXIV
                                 OPTION TO RENEW

         Tenant is hereby granted two (2) consecutive one (1) year options to
extend this lease upon the same terms and conditions contained herein (except
for the rent which shall be increased by 3% per year during each option year)
provided, however, that no default of which Landlord has notified Tenant exists
at the time of exercise any such options and remains uncured, unless Landlord
waives the existence of such default in writing. Such options shall be exercised
by written notice to Landlord not less than ninety (90) days prior to the
expiration of the initial term or the then current option term, as appropriate.


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<PAGE>
                                  ARTICLE XXV
                                  HOLDING OVER

         This Lease shall automatically terminate and be of no further force or
effect upon the expiration of the term or the expiration of the term of the
options (as the case may be) and any holding over by Tenant after such
expiration shall not constitute a renewal hereof or provide Tenant with any
rights hereunder except that Tenant shall be deemed to be in possession of the
Property on a month to month tenancy commencing on the first day following the
expiration of this lease and a tenant at sufferance of Landlord. Any such
tenancy shall be subject to the terms and conditions herein contained, except
that the monthly rent for the Premises shall be equal to double the monthly rent
as of the date of expiration of the term (or options as the case may be) and
said tenancy may be terminated at any time upon thirty (30) days' written notice
by Landlord to Tenant. The acceptance of rent under the provisions of this
Article XXV, shall not, however, be construed as a waiver by Landlord of any
rights under this Lease.

                                  ARTICLE XXVI
                                 ARTICLE TITLES

         The parties agree that the article titles are inserted only as a matter
of convenience and shall in no way define, limit or otherwise affect the scope
or intent of the particular articles to which they refer.

                                 ARTICLE XXVII
                                  SEVERABILITY

         The Articles and provisions of this Agreement are independent of and
separable from each other, and no Article or provision shall be affected or
rendered invalid or unenforceable by virtue of the fact that, for any reason,
any other Article or provision may be invalid or unenforceable in whole or in
part.

         IN WITNESS WHEREOF, the parties have executed this agreement on the
date first set forth above in San Juan, Puerto Rico.


                                              CORTELCO PUERTO RICO, INC.



                                              /s/ Francisco Sanchez
                                              ----------------------------------
                                              By:  Francisco Sanchez



                                              CORTELCO SYSTEMS PUERTO RICO, INC.



                                                 /s/ Sergio Moren
                                              ----------------------------------
                                              By:  Sergio Moren



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