SECOND AMENDMENT TO LEASE

         This SECOND  AMENDMENT  TO LEASE (the  "Agreement")  is made as of this
30th day of  August , 1999 by and  between  DALLAS  OFFICE  PORTFOLIO,  L.P.,  a
Delaware  limited   partnership   ("Landlord")  as  successor-in-   interest  to
GREENVILLE AVENUE PROPERTIES,  LTD.  ("Previous  Landlord") and PREFERRED VOICE,
INC.  having an address at 6500 Greenville  Avenue,  Suite 570,  Dallas,  Texas,
75206 ("Tenant").

                                   WITNESSETH:

         WHEREAS,  Landlord and Tenant  entered  into a Lease dated  February 3,
1998,  as amended  by that First  Amendment  to Lease  dated  March 1, 1999 (the
"Lease") with respect to the Premises  consisting of approximately  3,588 square
feet  ("Existing  Space")  known as Suite  570,  in the  building  known as 6500
Greenville  Place,  located at 6500  Greenville  Avenue,  Dallas,  Texas,  which
premises are more particularly described in the Lease; and;

         WHEREAS,  Landlord and Tenant now mutually desire to amend the Lease to
reflect (i) the addition of 2,535 square feet (the  "Expansion  Space") as shown
on  Exhibit  "B-2"  annexed  hereto  and made a part  thereof,  which  all space
combined  (including the Expansion  Space and Existing  Space) shall be known as
Suite 570,  consisting of 6,123 rentable  square feet as shown on Exhibit "B- 1"
annexed  hereto  and  made a part  hereof  (the  "Premises"),  and (ii) the then
subsequent  extension  of lease on the Existing  Space and to further  amend the
terms and conditions of the Lease as set forth below; and;

         NOW,  THEREFORE,  in  consideration  of  the  mutual  covenants  herein
contained,   and  other  good  and  valuable  consideration,   the  receipt  and
sufficiency  of which  are  hereby  acknowledged,  Landlord  and  Tenant  hereby
covenant and agree as follows:

         1. The provisions of this Agreement  shall  supersede any  inconsistent
provisions  contained  in the Lease,  regardless  of whether  such  inconsistent
provisions  are  contained  in the  printed  portion  of the  Lease or any rider
annexed  thereto and made a part thereof.  All  capitalized  items not otherwise
defined herein shall have the same meanings ascribed to them in the Lease.

         2. The Effective Date for the first 1,409rsf  ("First  Expansion Space"
refer to Exhibit B-2 for  location)  expansion  shall  commence  October 1, 1999
("Primary  Effective  Date")  and  subsequently,  the  Effective  Date  for  the
remaining  1,126rsf ("Second Expansion Space" refer to Exhibit B-2 for location)
shall commence January 1, 2000 ("Secondary Effective Date")

         3. A).Effective from and after the day following substantial completion
of the Work in the Existing Space and the First  Expansion  Space  ("Substantial
Completion Date" which is estimated to be September 30, 1999), Tenant shall then
occupy both the Existing Space and the First Expansion Space ("Primary Effective
Date").  Landlord  and Tenant  shall  confirm the Primary  Effective  Date in an
acceptance  letter or other written  instrument after the Primary Effective Date
within  fifteen (15) days of demand  therefore by Landlord,  provided,  however,
that the failure of  Landlord  and Tenant to execute  such letter or  instrument
shall not affect the  Primary  Effective  Date as  established  pursuant to this
Paragraph  3(A).  If the Primary  Effective  Date occurs on a day other than the
first  day of a  calendar  month,  rent  and  such  other  amounts  constituting
additional  rental  under the Lease with  respect to the First  Expansion  Space
shall be  prorated  on a per diem  basis  for the  month  in which  the  Primary
Effective Date shall occur.  Tenant  expressly  waives any right to rescind this
Agreement  or the Lease,  or any damages,  direct or indirect,  which may result
from  Landlord's  failure to deliver the First  Expansion Space by September 30,
1999. If Landlord  shall be unable to deliver to Tenant  possession of the First
Expansion  Space by September 30, 1999,  then rent for the Existing  Space shall
continue and rent for the First Expansion Space only shall abate for such period
as possession by Tenant is delayed unless Tenant shall cause such delay in which
case  rent  shall  not  abate  and rent for the  Existing  Space  and the  First
Expansion  Space shall commence  October 1, 1999 (according to the rent schedule
as addressed in  paragraph 5 below).  The  abatement of rent with respect to the
First  Expansion  Space,  does  constitute  full  settlement of all claims which
Tenant might  otherwise have against  Landlord by reason of the First  Expansion
Space not being ready for occupancy by September 30, 1999 and no such failure by
Landlord to deliver  possession  of the First  Expansion  Space shall  affect or
impair the validity of the Agreement or the Lease,  or the obligations of Tenant
hereunder or give rise to any claim for damages by Tenant or claim for

<PAGE>

rescission of this Agreement or the Lease.  Notwithstanding  anything  contained
herein to the  contrary,  if Landlord  is unable to deliver the First  Expansion
Space to Tenant by  September  30,  1999,  then the term of this Lease  shall be
extended  by the number of days of such  delay in  commencement  of the  Primary
Effective Date and the Base Annual Rent for that extension period shall be equal
to the per diem  rate  Tenant  paid  during  the  month of  December,  2003.  If
Substantial  Completion can be achieved  earlier than  September 30, 1999,  then
Landlord  shall give Tenant ten (10) days prior written  notice and Tenant shall
agree  to move  into the  First  Expansion  Space  the  next  morning  following
Substantial Completion and commence the Primary Effective Date on that date at a
daily rate (for the First Expansion  Space) of $61.76 for those days occupied by
Tenant prior to October 1, 1999.

                  B).Effective  from and  after  the day  following  substantial
completion of the Work in the Second  Expansion Space  ("Substantial  Completion
Date" which is defined as December 31, 1999),  Tenant shall then also occupy the
Second Expansion Space ("Secondary  Effective Date").  Landlord and Tenant shall
confirm the Secondary  Effective  Date in an acceptance  letter or other written
instrument after the Secondary Effective Date within fifteen (15) days of demand
therefore  by  Landlord,  provided,  however,  that the failure of Landlord  and
Tenant to execute  such  letter or  instrument  shall not  affect the  Secondary
Effective Date as established  pursuant to this Paragraph 3(B). If the Secondary
Effective  Date  occurs on a day other than the first day of a  calendar  month,
rent and such other amounts constituting  additional rental under the Lease with
respect to the Second  Expansion Space shall be prorated on a per diem basis for
the month in which the Secondary  Effective Date shall occur.  Tenant  expressly
waives any right to rescind this Agreement or the Lease, or any damages,  direct
or  indirect,  which may result  from  Landlord's  failure to deliver the Second
Expansion  Space by December 31, 1999. If Landlord shall be unable to deliver to
Tenant  possession of the Second Expansion Space by December 31, 1999, then rent
for the Existing Space and the First Expansion Space shall continue and rent for
the Second  Expansion  Space only shall abate for such period as  possession  by
Tenant is delayed  unless Tenant shall cause such delay in which case rent shall
not abate and rent for the Second  Expansion  Space  shall  commence  January 1,
2000.  The abatement of rent with respect to the Second  Expansion  Space,  does
constitute  full  settlement  of all claims which Tenant  might  otherwise  have
against  Landlord  by reason of the Second  Expansion  Space not being ready for
occupancy  by  December  31,  1999 and no such  failure by  Landlord  to deliver
possession of the Second  Expansion Space shall affect or impair the validity of
the Agreement or the Lease, or the obligations of Tenant  hereunder or give rise
to any claim for damages by Tenant or claim for  rescission of this Agreement or
the  Lease.  Notwithstanding  anything  contained  herein  to the  contrary,  if
Landlord is unable to deliver the Second  Expansion  Space to Tenant by December
31, 1999, then the term of this Lease shall be extended by the number of days of
such delay in commencement  of the Secondary  Effective Date and the Base Annual
Rent for that  extension  period shall be equal to the per diem rate Tenant paid
during the month of December,  2003.  If Tenant should wish to occupy the Second
Expansion Space earlier than January 1, 2000, Tenant shall then give Landlord 45
days  prior  written  notice  of such  request,  and  within  10 days  following
Landlord's notice of early  commencement,  sign Landlord's  document  signifying
such  early  required  commencement.   If  Landlord  is  then  able  to  achieve
Substantial  Completion earlier than December 31, 1999, then Landlord shall give
Tenant ten (10) days prior written  notice and Tenant shall agree to move in the
morning following  Substantial  Completion and commence the Secondary  Effective
Date on that date at a daily rate (for the Second Expansion Space) of $49.36 for
those days prior occupied by Tenant to January 1, 2000.

         4. Upon Tenant's  execution  thereof,  Tenant shall pay to Landlord the
sum of  $3,578.58  to be held by Landlord  as  additional  security  pursuant to
Article 6 of the Fundamental Lease Provisions of the Lease, for a total Security
Deposit held of $8,512.08.

         5.  Effective  from and after  October 1, 1999,  Base Annual  Rent,  as
reflected in Article 4 of the Fundamental Lease Provisions shall be:

                           *October 1, 1999  -December  31,  1999:$6,662.67  per
                           month January 1, 2000-December 31, 2000:$8,357.90 per
                           month January 1, 2001-December 31, 2001:$8,613.02 per
                           month January 1, 2002-December 31, 2002:$8,674.25 per
                           month January 1, 2003 -December 3 1, 2003:$ 8,929.3 8
                           per month

* If the Primary or Secondary Effective Dates should commence prior to the dates
specified in  paragraphs  3(A) and (B) above,  then the monthly  rental shall be
adjusted as provided for therein.

<PAGE>

         6. For and in consideration of the covenants  contained in the Lease to
which this  Agreement  has been made a part,  Landlord and Tenant agree that the
ending date, as defined in Paragraph  (3) of the  Fundamental  Lease  Provisions
section of the Lease shall become December 31, 2003,  unless otherwise  adjusted
as detailed in paragraphs 3(A) & 3(B) above.

         7. (A) Landlord,  at its sole cost and expense,  shall  provide  Tenant
requested  improvements (the "Improvements") to the Existing Space and the First
Expansion  Space only, in a building  standard manner for a cost to Landlord not
to  exceed  $16.986.59  ("Landlord's  Primary  Allowance")  and  in  the  manner
specified in Exhibit  "A-1" ("Work  Letter") and the  contractor's  bid (Exhibit
A-2)  herein  attached.  In the event the cost of  completing  the  Improvements
exceeds Landlord's Allowance or if Tenant makes any changes to the Improvements,
Tenant  expressly  agrees that the costs  attributable to those changes shall be
the sole  responsibility  of Tenant and Tenant  shall pay same to Landlord  upon
demand  as  specified  in  Exhibit  A-1.  Except  for the  Improvements,  Tenant
acknowledges  and agrees that it has made a full and complete  inspection of the
Existing  Space and the First  Expansion  Space and accepts  such in its present
"as-is"  condition as suitable for Tenant's  intended use and  occupancy  and/or
continued  occupancy  thereof.  Upon Tenant's  possession of the First Expansion
Space,  it shall be  conclusively  presumed  that same has been so  accepted  by
Tenant,  is in  satisfactory  conditions  and  complies  fully  with  Landlord's
covenants and obligations.

                  (B)  Landlord,  at its sole cost and  expense,  shall  provide
Tenant requested improvements (the "Improvements") to the Second Expansion Space
only,  in a  building  standard  manner  for a cost to  Landlord  not to  exceed
$12,795.15  ("Landlord's  Secondary  Allowance") and in the manner  specified in
Exhibit  "A-3" ("Work  Letter") and the  contractor's  bid (Exhibit  A-4) herein
attached.  In  the  event  the  cost  of  completing  the  Improvements  exceeds
Landlord's Allowance or if Tenant makes any changes to the Improvements,  Tenant
expressly agrees that the costs  attributable to those changes shall be the sole
responsibility  of Tenant and Tenant  shall pay same to Landlord  upon demand as
specified in Exhibit A-3. Except for the Improvements,  Tenant  acknowledges and
agrees that it has made a full and complete  inspection of the Second  Expansion
Space and accepts such in its present "as-is" condition as suitable for Tenant's
intended use and  occupancy  thereof.  Upon  Tenant's  possession  of the Second
Expansion  Space,  it  shall  be  conclusively  presumed  that  same has been so
accepted  by Tenant,  is in  satisfactory  conditions  and  complies  fully with
Landlord's covenants and obligations.

         8. Tenant  expressly  warrants and represents that the sole brokers who
negotiated  and  brought  about this  transaction  was  Transwestern  Commercial
Services  ("Landlord's  Agent") and Swearingen Realty Group ("Tenant's  Agent").
Tenant  represents it neither  consulted nor  negotiated  with any brokers other
than those named herein with regard to the Promises. Tenant agrees to indemnify,
defend  and save  Landlord  harmless  from and  against  any  claims for fees or
commissions  from anyone or any entity other than those  brokers  named  herein,
with whom Tenant has dealt in  connection  with this  Agreement.  The  foregoing
provisions  contained in this  Paragraph 8 shall survive the expiration or early
termination of the Lease.

         9. (A) Effective from and after the Primary  Effective  Date,  Tenant's
parking as referred to in Section 12 of the Fundamental  Lease  Provisions shall
be amended  to read:  "A total of four (4)  Garage  parking  spaces at no charge
during the term and eleven (11) Lot spaces at no charge during the term,  all on
a first come first serve basis."

                  (B)  Effective  from and after the Secondary  Effective  Date,
Tenant's  parking  as  referred  to in  Section  12  of  the  Fundamental  Lease
Provisions  shall be amended to read: "A total of six (6) Garage  parking spaces
at no charge during the term and  seventeen  (17) Lot spaces at no charge during
the term, all on a first come first serve basis."

         10. Effective from and after the Primary and Secondary Effective Dates,
#10 of the First  Amendment  to Lease  shall be  modified  to include the entire
Premises  (including  the  Existing  Space,  the First  Expansion  Space and the
Secondary Expansion Space) so that Landlord's Annual Operating Cost Contribution
(as addressed in Section 5 of the Fundamental  Lease Provisions) shall be Actual
Expenses for Calendar Year 1999 for building standard  services,  with no cap of
any kind.

         11.  Effective  from and after the Primary  Effective  Date, #11 of the
First  Amendment  to Lease shall become null and void and Tenant shall no longer
have any Right of First Refusal under this lease.

Dallas1 571383 v 1, 99999.00001

<PAGE>



         12. This  Agreement  shall not  constitute an Agreement by Landlord and
shall not be binding  upon  Landlord  unless and until this  Agreement  shall be
executed by Landlord and Tenant and shall be delivered by Landlord to Tenant.

         13. This Agreement may not be changed orally, and shall be binding upon
and shall  inure to the benefit of the parties to it,  their  respective  heirs,
successors and, as permitted, their assigns.

         14.      Except  as  hereby  modified  or  amended,  all  of the terms,
covenants  and conditions of the Lease shall remain unmodified and in full force
and effect.

         IN  WITNESS  WHEREOF,  Landlord  and  Tenant  have duly  executed  this
Agreement as of the day and year first above written.

LANDLORD:                                                  TENANT:

Dallas Office Portfolio, L.P.,                             Preferred Voice, Inc.
a Delaware limited partnership

By: Suburban Dallas Office Portfolio, LLC,
    a Delaware limited liability company, its
    sole general partner

  By:  Beacon Capital Partners, L.P., a Delaware
       limited partnership, its sole member

      By:  Beacon Capital Partners, Inc., a Maryland
           corporation, its sole general partner

         By:  /s/ E. Valker Wheeler                     By:   /s/ Mary Merritt
              ---------------------                           ------------------
              Name: E. Valker Wheeler                         Name: Mary Merritt
              -----------------------                         ------------------
              Title: S.V.P.                                   Title: VP Finance
              -------------                                   ------------------
                                                              Hereunto Duly
                                                              Authorized

Date Signed: 8/30/99                                         Date Signed:8/25/99
            --------                                                     -------

<PAGE>

                                  EXHIBIT "A-1"

                                   WORK LETTER

                                       TO

                             OFFICE LEASE AGREEMENT

                                     BETWEEN

                           DALLAS OFFICE PORTFOLIO, L.P.,
                           a Delaware limited partnership
                                       AND

                              PREFERRED VOICE, INC.

         This  Exhibit  sets  forth  the  respective  obligations  of,  and  the
procedures to be followed by, Landlord and Tenant in the design and construction
of those  improvements  that will  prepare the  Existing  Premises and the First
Expansion  Space  described  in Exhibit B-2 of the Lease for Tenant's use and/or
continued occupancy.

1.       The Work.
         --------

         The "Work" will  consist of  leasehold  improvements  described  in the
floor plan and  specifications  attached  to this Lease as Exhibit  C-1  ("Final
Plan-1").

         B. Landlord  will pay all costs and fees  incurred in  connection  with
construction  of the leasehold  improvements as described in the Final Plan-1 up
to a cost of  $16,986.59.  Tenant  will  pay all  costs  and  fees  incurred  in
connection  with  preparation of plans and working  drawings (if should later be
required) and construction  resulting from a change requested by Tenant pursuant
to Paragraph 2 of this Exhibit and any amount in excess of  $16,986.59  incurred
by  Landlord  in  connection  with  the  design  and  construction  of the  Work
(collectively,   "Tenant's  Cost").  Tenant's  Cost  hereunder  will  be  deemed
additional rent under the Lease.

2.       Changes.
         -------

         A. If Tenant desires any changes, alterations or additions to the Final
Plan-1,  Tenant must  submit a detailed  written  request to  Landlord  ("Change
Order").  If reasonable and practicable and generally  consistent with the Final
Plan-1 previously approved,  Landlord will comply with the Change Order, but all
costs in connection  therewith,  including  without  limitation  any  additional
plans,  drawings and engineering  reports or opinions or  modifications  of such
existing items, will be paid for by Tenant.  Landlord may at any time reasonably
estimate Tenant's Cost for a Change Order, in advance,  and, Tenant will deposit
the  estimated  amount with  Landlord  within five (5) days after  requested  by
Landlord.  If such estimated  amount exceeds the actual amount of Tenant's Cost,
Tenant will receive a refund of the difference, and if the actual amount exceeds
the estimated amount, Tenant will pay the difference to Landlord within five (5)
days  after  requested  by  Landlord.  If  any  additional  plans,  drawings  or
specifications,  or  modifications  of such items,  are  required to construct a
Change Order, the same will be prepared (at Tenant's cost by Tenant's architect)
and approved in the manner  described  above.  Under no  circumstances  will any
Change Orders serve to abate the rentals under the Lease.

3.       Substantial Completion.
         ----------------------

         A. Landlord will be deemed to have  "substantially  completed" the Work
for the purposes  thereof if Landlord has caused all of the Work to be completed
substantially  except for so called "punch list items,"  e.g.,  minor details of
construction or decoration or mechanical  adjustments which do not substantially
interfere with Tenant's  occupancy of the First Expansion space and/or continued
occupancy of Existing  Premises to be made by Tenant. If there is any dispute as
to  whether  Landlord  has  substantially  completed  the Work,  the good  faith
decision of Landlord's architect will be final and binding on the parties.

         B.  If  Landlord   notifies   Tenant  in  writing   that  the  Work  is
substantially  completed,  and Tenant fails to object  thereto in writing within
three (3) days  thereafter  specifying  in  reasonable  detail the items of Work
needed to be  performed  in order for  substantial  completion,  Tenant  will be
deemed conclusively to have agreed that the Work is substantially completed, for
purposes of commencing rental under the Lease.

<PAGE>

         C. Substantial completion will not prejudice Tenant's rights to require
full completion of any remaining items of Work.  However,  if Landlord  notifies
Tenant in writing that the Work is fully  completed,  and Tenant fails to object
thereto in writing within fifteen (15) days thereafter  specifying in reasonable
detail the items of work needed to be completed and the nature of work needed to
complete  said items,  Tenant will be deemed  conclusively  to have accepted the
Work as fully completed (or such portions  thereof as to which Tenant has not so
objected).

4.       Construction.
         ------------

         A.       Landlord reserves the right to substitute comparable or better
materials and items for those shown in the attached Final Plan-1.

         B. Landlord warrants that Landlord will employ an experienced, licensed
contractor  to  construct  the  leasehold  improvements  and will require in the
construction contract that such contractor construct the leasehold  improvements
in a good and  workmanlike  manner and in compliance  with all applicable  laws,
ordinances  and  building  codes;  provided,  however,  Tenant  will  be  solely
responsible  for  determining  whether or not  Tenant is a public  accommodation
under The Americans with Disabilities Act and Texas  Architectural  Barriers Act
and whether or not the Final Plan-1  complies with such laws and the regulations
thereunder.

5.       Liability.
         ---------

         The parties  acknowledge that Landlord is not an architect or engineer,
and  that the Work  will be  performed  by  Landlord's  independent  contractor.
Accordingly,  Landlord does not guarantee or warrant that the Final Plan- 1 will
be free from errors or  omissions,  nor that the Work will be free from defects,
and  Landlord  will have no  liability  therefor.  In the event of such  errors,
omissions, or defects, by the independent contractor, Landlord will cooperate in
any action Tenant desires to bring against such party.

6.       Incorporation Into Lease: Default .
         ----------------------------------

         THE  PARTIES  AGREE  THAT THE  PROVISIONS  OF THIS  EXHIBIT  ARE HEREBY
INCORPORATED BY THIS REFERENCE INTO THE LEASE FULLY AS THOUGH SET FORTH THEREIN.
In the event of any express  inconsistencies between the Lease and this Exhibit,
the latter  will  govern and  control.  Any  default  by Tenant  hereunder  will
constitute a default by Tenant under the Lease and Tenant will be subject to the
remedies and other provisions applicable thereto under the Lease.

INITIALED FOR                                             INITIALED FOR
IDENTIFICATION:                                           IDENTIFICATION:
BY LANDLORD:                                              BY TENANT:

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

<PAGE>

                                  EXHIBIT "A-2"

                                CONTRACTOR'S BID

                       [chart outlining break-down of bid]

<PAGE>

                                 EXHIBIT "A-3"

                                   WORK LETTER

                                       TO

                             OFFICE LEASE AGREEMENT

                                     BETWEEN

                           DALLAS OFFICE PORTFOLIO, L.P.,
                          a Delaware limited partnership
                                       AND

                              PREFERRED VOICE, INC.

         This  Exhibit  sets  forth  the  respective  obligations  of,  and  the
procedures to be followed by, Landlord and Tenant in the design and construction
of those  improvements that will prepare the Second Expansion Space described in
Exhibit B-2 of the Lease for Tenant's use and occupancy.

1.       The Work.
         --------

         The "Work" will  consist of  leasehold  improvements  described  in the
floor plan and  specifications  attached  to this Lease as Exhibit  C-2  ("Final
Plan-2").

         B. Landlord  will pay all costs and fees  incurred in  connection  with
construction  of the leasehold  improvements as described in the Final Plan-2 up
to a cost of  $12,795.  15.  Tenant  will pay all  costs  and fees  incurred  in
connection  with  preparation of plans and working  drawings (if should later be
required) and construction  resulting from a change requested by Tenant pursuant
to Paragraph 2 of this Exhibit and any amount in excess of  $12,795.15  incurred
by  Landlord  in  connection  with  the  design  and  construction  of the  Work
(collectively,   "Tenant's  Cost").  Tenant's  Cost  hereunder  will  be  deemed
additional rent under the Lease.

2.       Changes.
         -------

         A. If Tenant desires any changes, alterations or additions to the Final
Plan-2,  Tenant must  submit a detailed  written  request to  Landlord  ("Change
Order").  If reasonable and practicable and generally  consistent with the Final
Plan-2 previously approved,  Landlord will comply with the Change Order, but all
costs in connection  therewith,  including  without  limitation  any  additional
plans,  drawings and engineering  reports or opinions or  modifications  of such
existing items, will be paid for by Tenant.  Landlord may at any time reasonably
estimate Tenant's Cost for a Change Order, in advance,  and, Tenant will deposit
the  estimated  amount with  Landlord  within five (5) days after  requested  by
Landlord.  If such estimated  amount exceeds the actual amount of Tenant's Cost,
Tenant will receive a refund of the difference, and if the actual amount exceeds
the estimated amount, Tenant will pay the difference to Landlord within five (5)
days  after  requested  by  Landlord.  If  any  additional  plans,  drawings  or
specifications,  or  modifications  of such items,  are  required to construct a
Change Order, the same will be prepared (at Tenant's cost by Tenant's architect)
and approved in the mariner  described above.  Under no  circumstances  will any
Change Orders serve to abate the rentals under the Lease.

3.       Substantial Completion.
         ----------------------

         A. Landlord will be deemed to have  "substantially  completed" the Work
for the purposes  thereof if Landlord has caused all of the Work to be completed
substantially  except for so called "punch list items,"  e.g.,  minor details of
construction or decoration or mechanical  adjustments which do not substantially
interfere with Tenant's  occupancy of the Second  Expansion  space to be made by
Tenant.  If  there is any  dispute  as to  whether  Landlord  has  substantially
completed  the Work,  the good faith  decision of Landlord's  architect  will be
final and binding on the parties.



<PAGE>



4.       Construction.
         ------------

         A.       Landlord reserves the right to substitute comparable or better
materials and items for those shown in the attached Final Plan-2.

         B. Landlord warrants that Landlord will employ an experienced, licensed
contractor  to  construct  the  leasehold  improvements  and will require in the
construction contract that such contractor construct the leasehold  improvements
in a good and  workmanlike  manner and in compliance  with all applicable  laws,
ordinances  and  building  codes;  provided,  however,  Tenant  will  be  solely
responsible  for  determining  whether or not  Tenant is a public  accommodation
under The Americans with Disabilities Act and Texas  Architectural  Barriers Act
and whether or not the Final Plan-2  complies with such laws and the regulations
thereunder.

5.       Liability..
         ---------

         The parties  acknowledge that Landlord is not an architect or engineer,
and  that the Work  will be  performed  by  Landlord's  independent  contractor.
Accordingly,  Landlord  does not guarantee or warrant that the Final Plan-2 will
be free from errors or  omissions,  nor that the Work will be free from defects,
and  Landlord  will have no  liability  therefor.  In the event of such  errors,
omissions, or defects, by the independent contractor, Landlord will cooperate in
any action Tenant desires to bring against such party.

6.       Incorporation Into Lease: Default.
         ---------------------------------

         THE  PARTIES  AGREE  THAT THE  PROVISIONS  OF THIS  EXHIBIT  ARE HEREBY
INCORPORATED BY THIS REFERENCE INTO THE LEASE FULLY AS THOUGH SET FORTH THEREIN.
In the event of any express  inconsistencies  between the Lease and this Exhibit
the latter  will  govern and  control.  Any  default  by Tenant  hereunder  will
constitute a default by Tenant under the Lease and Tenant will be subject to the
remedies and other provisions applicable thereto under the Lease.

         INITIALED FOR                                  INITIALED FOR
         IDENTIFICATION                                 IDENTIFICATION
         BY LANDLORD:                                   BY TENANT:

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


<PAGE>

                            Exhibits "C-1" and "C-2"

               [Graphics of site plans or layout of leased spaces]