EXHIBIT 10.17


                            FIRST AMENDMENT TO LEASE


This FIRST  AMENDMENT TO LEASE (the  "Agreement")  is made as of this 1st day of
March 1999 by and  between  DALLAS  OFFICE  PORTFOLIO,  LP, 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 (the
"Lease") with respect to the Premises  consisting of approximately  1,707 square
feet  ("Existing  Space")  know 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 1,881  square  feet (the  "Expansion  Space")  as shown on
Exhibit  "B-2" annexed  hereto and made a part thereof (ii) the then  subsequent
extension of lease on the Existing  Space,  which all space combined  (including
the Expansion  Space and Existing Space shall be known as Suite 570,  consisting
of 3,588 rentable  square feet as shown on Exhibit "B-1" annexed hereto and made
a part hereof  (the"Premises")  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 term of  this Agreement shall  commence March 1,  1999  upon the
conditions set forth herein.

         3. On approximately March 5, 1999, Tenant shall surrender unto Landlord
the Existing Space and relocate into the Expansion  Space,  so that Landlord may
perform the Work specified in Exhibit A-Work Letter.  At such time, Tenant shall
occupy the Expansion Space in accordance  with all of the applicable  provisions
of the Lease.

         Effective  from and after the day following  substantial  completion of
the Work in the Existing Space ("Substantial Completion Date" which is estimated
to be March 31, 1999),  Tenant shall then occupy both the Existing space and the
Expansion Space ("Effective Date"). Landlord and Tenant


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shall  confirm  the  Effective  Date in an  acceptance  letter or other  written
instrument after the 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  Effective  Date as
established  pursuant to this Paragraph 3. If the 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  Existing
Space shall be prorated on a per diem basis for the month in which the Effective
Date shall occur. Tenant expressly waives any right to rescind this Agreement or
the Lease, or any damages, direct or indirect,  winch may result from Landlord's
failure to deliver the Existing  Premises by April 1, 1999. If Landlord shall be
unable to deliver to Tenant  possession  of the Existing  Space by April 1,1999,
then rent for the Expansion  Space shall continue and rent for the Existing Spam
only shall  continue to abate (as is  reflected  in  paragraph 5 below) 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  entire  Premises  shall
commence April 1, 1999. The  continuation  of the abatement of rent with respect
to the Existing Space, does constitute full settlement of all claim which Tenant
might otherwise have against  Landlord by reason of the Existing Space not being
ready for  occupancy by April 1, 1999 and no such failure by Landlord to deliver
possession  of the  Existing  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 Existing  Space to Tenant by April 1, 1999,  then the term
of this  Lease  shall  be  extended  by the  number  of days  of such  delay  in
commencement  of the 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
April, 2002.

         4. Upon Tenant's  execution  thereof,  Tenant shall pay to Landlord the
sum of $523.75 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 $4,933.50.

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

       March 1, 1999 - March 5,1999:                        $2,276.00 per month
       March 6,1999 - Substantial Completion Date           $2,508.00 per month
       *Effective Date - Month 12                           $4,784.00 per month
       Month 13  - Month 24                                 $4,933.50 per month
       Month 25 - Month 36                                  $5,083.00 per month

*Month  12 shall  mean  through  the last day of the 12th  full  calendar  month
following  the Effective  Date.  Month 24 shall mean through the last day of the
24th full  calendar  month  following  the  Effective  Date.  Month 36 shall mom
through the last day to the 36th full  calendar  month  following  the Effective
Date.

         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 April 30, 2002,  unless otherwise  adjusted as
detailed in paragraph 3 above.



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         7.  Landlord,  at its  sole  cost and  expense,  shall  provide  Tenant
requested  improvements  (the  "Improvements")  to the Existing Space only, in a
building  standard  manner  for  a  cost  to  Landlord  not  to  exceed  $12,248
("Landlord's  Allowance")  and in the manner  specified  in  Exhibit  "A" ("Work
Letter") and the contractor's  bid (Exhibit A-1) 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.
Except for the Improvements,  Tenant  acknowledges and agrees that it has made a
fall and complete  inspection  of the  Existing  Space and the  Expansion  Space
(Premises)  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  complete  possession  of the  "Premises",  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 broker who
negotiated and brought about this transaction was Transwestern  Property Company
("Landlord's  Agent") and Swearingen  Realty Group  ("Tenant's  Agent").  Tenant
represents it neither  consulted nor negotiated with any broker other than those
named herein with regard to the Premises. Tenant agrees to indemnify, defend and
save Landlord  harmless from and against any claims for fees or commissions from
anyone or my 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. Effective  from and after the Effective  Date,  Tenant's  parking as
reflected to in Section 12 of the Fundamental  Lease Provisions shall be amended
to read:  "A total of three (3) Garage  parking  spaces at no charge  during the
term and eight (8) Lot spaces at no charge during the term,  all on a first come
first serve  basis.  Tenant  shall no longer be  entitled to one (1)  additional
unreserved garage parking space on a month to month basis."

         10.  Effective  from and after  the  Effective  Date,  Section 5 of the
Fundamental Lease Provisions shall change from "1998" to "1999".

         11.  Effective from and after the Effective  Date,  subject to Tenant's
then current  financials,  prior right of first refusal (if any),  prior renewal
options (if any),  and as long as Tenant is not or has not been in default under
the Lease, and has not subleased or assigned all or any portion of the Premises,
then Tenant shall have a one-time Right of First Refusal on approximately  1,000
square  feet (as  shown on  attached  Exhibit  "D"-"Refusal  Space")  under  the
following terms and conditions:

         1)       Tenant  must  agree to at least the same total  lease  package
                  being  offered to a bona- fide third party but in no case less
                  than the base rental Tenant is contracted to pay.

         2)       Landlord shall give notice  ("Refusal  Notice") to Tenant of a
                  bona-fide  offer for the refusal  space and Tenant  shall then
                  have three (3) business days in which to accept or reject said
                  offer.



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         3)       If Tenant should reject  Landlord's offer (or if such offer is
                  not  accepted  in writing  within the three (3)  business  day
                  period, then Tenant's Right of First Refusal shall become null
                  and void,

         4)       If Tenant  accepts  said offer,  Tenant  must  execute a lease
                  modification  covering  such  space  within  seven (7) days of
                  receipt  related  paperwork  from Landlord  under the term and
                  conditions  specified  in the  offer  or  Tenant  shall  be in
                  default under the Lease.

         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.

         19. 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.

         20. 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/ Illegible                                     By:/s/ Mary Merritt
   ---------------------------------                    ------------------------
   Name:Illegible                                       Name:Mary Merritt
        ----------------------------                         -------------------
   Title                                                Title: VP Finance
          --------------------------                          ------------------
                                                        Hereunto Duly Authorized

Date Signed:3/1/99                                      Date Signed:2/26/99
            ------------------------                                ------------

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                                   EXHIBIT "A"


                                   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 described in Exhibit B-1 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 "(Final
Plan").

B. Landlord will pay all costs and fees incurred in connection with construction
of the  leasehold  improvements  as  described in the Final Plan up to a cost of
$12,248.  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 $12,248  incurred  by  Landlord in
connection with the design and construction of the Work (collectively, "Tenant's
Cost"). Tenants 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,  Tenant  must  submit a  detailed  written  request to  Landlord  ("Change
Order").  If reasonable and practicable and generally  consistent with the Final
Plan 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  item, win 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.



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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  "punchlist  items," e.g.,  minor details of
construction or decoration or mechanical  adjustments winch do not substantially
interfere with Tenant's  occupancy of the New 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 Landlords  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.


         C. Substantial completion will not prejudice Tenant's rights to require
fill 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.

         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  budding  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  Working  Drawings  comply  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 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,


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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 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:
/s/                                                  /s/
------------------------------                       ---------------------------


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                                   EXHIBIT B-1

                              [Graphic of Premises]


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                                   EXHIBIT B-2

                          [Graphic of Expansion Space]


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                                    EXHIBIT C

                             [Graphic of Final Plan]


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                                    EXHIBIT D

                           [Graphic of Refusal Space]


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