Document:

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                                                                   Exhibit 10.14

                   FIRST AMENDMENT TO OFFICE LEASE AGREEMENT

STATE OF TEXAS
COUNTY OF DALLAS

     THIS FIRST AMENDMENT TO OFFICE LEASE AGREEMENT (this "First Amendment")
is made and entered into effective as of November 1, 1997, by and between
Collins Campbell Joint Venture ("Landlord") and telecom technologies, inc.
("Tenant").

                                R E C I T A L S

     WHEREAS, Landlord and Tenant entered into that certain Office Lease
Agreement dated as of April 4, 1997 (the "Lease") concerning certain Premises
defined therein and commonly known as Suite 3000 at 1701 North Collins Blvd.,
Richardson, Dallas County, Texas, which Lease is incorporated herein by
reference; and

     WHEREAS, Landlord and Tenant desire to amend the Lease to increase the
size of the First Portion of the Premises and to decrease the size of the
Second Portion of the Premises and to increase the Basic Rental.

     NOW, THEREFORE, in consideration of the mutual agreements herein set
forth, the mutual agreements set forth in the Lease, and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, Landlord and Tenant have agreed, and do hereby agree, as follows:

     1.   All terms capitalized herein and not specifically defined shall have
the same meaning herein as is ascribed to them in the Lease.

     2.   In Section 1. (c), "Premises", the rentable area in the leased
Premises is increased to 20,227 square feet of rentable area. The First Portion
of the Premises is increased in size to 14,277 square feet of rentable area
(highlighted in yellow on Exhibit A) and the Second Portion of the Premises is
decreased in size to 5,950 square feet of rentable area (highlighted in blue on
Exhibit A) described on Exhibit A attached hereto and incorporated herein for
all purposes. The total rentable area of the building is now stipulated for all
purposes herein to be 56,991 square feet of rentable area.

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     3.   In Section 1.(d), "Lease Term", is changed to sixty (60) months,
commencing on November 1, 1997 (the "Commencement Date") and ending on
October 31, 2002.

     4.   In Section 1.(e), "Basic Rental", is increased to $2,026,933.47.

     5.   In Section 1.(f), "Monthly Rental Installment", is changed to:

          Monthly from November 1, 1997 through March 31, 1998 - $23,497.56;
          then
          Monthly from April 1, 1998 through October 31, 1998 - $33,290.27;
          then
          Monthly from November 1, 1998 through October 31, 2002 - $34,925.29;
          then

     6.   In Section 3, "Rent", Paragraph 2 is changed to read as follows:

          14.818 months of basic rental, to be applied to the first fifteen
          monthly basic rental installments accruing hereunder, totaling
          $448,927.50 ("Prepaid Rent"), together with the security deposit (as
          defined in

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          Paragraph 1(g) hereof), shall be payable by Tenant to Landlord in
          two lump sum payments. $241,880.42 will be due contemporaneously with
          the execution hereof.  $224,463.75 will be due upon the later of June
          1, 1997, or commencement of construction by Landlord of the work
          described in the Work Letter Agreement.  Landlord will deposit the
          Prepaid Rent and Security Deposit in an escrow account with State
          Bank & Trust to be held until occupancy of the First Portion of the
          Premises by Tenant, at which time the Prepaid Rent and Security
          Deposit will become the property of Landlord remaining in the escrow
          account, which escrow account shall be debited monthly as basic
          rental accrues. On the first day of the fifteenth month following the
          date on which basic rent begins to accrue under this lease, Tenant
          shall pay $6,368.07. On the first day of the sixteenth month
          following the date on which basic rental begins to accrue under this
          lease, Tenant shall begin paying the scheduled monthly rental
          installment of $34,925.29 without demand and shall continue paying
          such monthly rental installments on or before the first day of each
          succeeding calendar month during the term hereof.

     7.   Exhibit C, "Work Letter Agreement", Section 7, "Payment of Costs;
Credit", line 7, the number $18.50 is increased to $23.75.

     8.   Except as herein provided to the contrary, Tenant's lease of the
          premises from Landlord pursuant hereto shall be on the same terms and
          conditions as those specified in the Lease.

     9.   The Lease (as amended by this First Amendment) remains in full force
and effect and is hereby ratified and affirmed.

     IN WITNESS WHEREOF, this First Amendment is hereby executed effective as
of the day and year first set forth above.

                                   LANDLORD:

                                   COLLINS CAMPBELL JOINT VENTURE,
                                     a Texas general partnership

                                   By: Jaytex Properties, Ltd.,
                                         a Texas limited partnership

                                       By: JRS Management, Inc.

                                            /s/ W. T. Field
                                           ---------------------------
                                            W. T. Field, President

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                                    TENANT:

                                    telecom technologies, inc.,
                                     a Texas corporation

                                    By: /s/ Anousheh Ansari
                                        ------------------------------
                                        Anousheh Ansari, President

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[Floor Plan Third Floor]<PAGE>

                                                                   Exhibit 10.15

                   SECOND AMENDMENT TO OFFICE LEASE AGREEMENT

     THIS SECOND AMENDMENT TO OFFICE LEASE AGREEMENT (this "Second
Amendment") is made and entered into effective as of July 1, 1998, by and
between Collins Campbell Joint Venture, ("Landlord") and telecom
technologies, inc.  ("Tenant").

                               R E C I T A L S
                               ---------------

     WHEREAS, Landlord and Tenant entered into that certain Office Lease
Agreement dated as of April 4, 1997 and amended as of November 1, 1997 (the
"Lease"), with respect to certain Premises defined therein and commonly known
as Suite 3000 at 1701 North Collins Blvd., Richardson, Dallas County, Texas,
which Lease is incorporated herein by reference; and

     WHEREAS, Landlord and Tenant desire to further amend the Lease to
increase the size of the Premises and increase the Basic Rental;

     NOW, THEREFORE, in consideration of the mutual agreements herein set
forth, the mutual agreements set forth in the Lease, and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, Landlord and Tenant have agreed, and do hereby agree, as
follows:

     1.  All terms used herein and not specifically defined shall have the same
         meaning herein as is ascribed to them in the Lease.

     2.  The Premises are hereby increased to 31,944 square feet of rentable
         area by adding 11,717 square feet of rentable area on the second
         floor, the "Expansion Space" described on Exhibit "A", which is
         attached hereto and incorporated herein for all purposes.

     3.  Basic Rental is increased to $3,061,979.54.

     4.  The monthly rental installment" is increased as set forth below:

         Monthly from July 1, 1998 through October 31, 1998-$44,286.10; then
         Monthly from November 1, 1998 through October 31, 2002-$54,746.55.

     5.  Landlord agrees to install, in accordance with the Work Letter
         Agreement attached hereto as Exhibit "C", the improvements described
         in Exhibit "C". Landlord has made no representations as to the
         condition of the Premises or the Building, or Landlord's undertaking
         to remodel, repair or decorate, except as expressly set forth herein
         and in Exhibit "C".

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     6.  Except as herein provided to the contrary, Tenant's lease of the
         Premises from Landlord pursuant hereto shall be on the same terms and
         conditions as those specified in the Lease.

     7.  The Lease (as amended by this First Amendment) remains in full force
         and effect and is hereby ratified and affirmed.

     8.  All other terms and conditions of the Lease shall remain unchanged and
         in full force and effect.

     9.  Special Provisions: Exhibits "A" and "C". Exhibit "B" was
         intentionally omitted.

     IN WITNESS WHEREOF, this Second Amendment is hereby executed effective as
of the day and year first set forth above.

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Second Amendment to Office Lease Agreement
Page 2 of 2

                                    LANDLORD:

                                    COLLINS CAMPBELL JOINT VENTURE
                                     a Texas general partnership

                                    By: Jaytex Properties, Ltd.,
                                         a Texas limited partnership

                                        By: JRS Management, Inc.

                                            By: /s/ W. T. Field
                                                ---------------------------
                                                W. T. Field, President

                                    TENANT:
                                    telecom technologies, inc.,
                                      a Texas corporation

                                    By: /s/ Anousheh Ansari
                                        -----------------------------------
                                        Anousheh Ansari, President

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                                   Exhibit A

[Diagram of 2nd Level Floor Plan]

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                                  EXHIBIT "C"

                             WORK LETTER AGREEMENT

telecom technologies, inc.
1701 North Collins Blvd.
Suite 3000
Richardson, Texas 75080

Re:  Suite 2000, 1701 North Collins Blvd., The Atrium on Collins Phase II,
     Richardson, Texas.

Dear Anousheh:

     You (hereinafter referred to as "Tenant") and we (hereinafter referred to
as "Landlord") are executing, simultaneously with this "Work Letter Agreement"
(herein so called), a written Second Amendment to Office Lease Agreement (the
"Second Amendment") covering the space referred to above (herein after called
the "Expansion Space").

     To induce Tenant to enter into such Second Amendment (which is hereby
incorporated by reference) and in consideration of the mutual covenants
hereinafter contained, Landlord and Tenant mutually agree as follows:

     1.   Final Plans. Landlord agrees to provide, by Landlord's designated
space planner, architect and/or engineer, the following Building Standard
(hereinafter defined) space plans and architectural and mechanical drawings and
specifications (hereinafter collectively referred to as the "Final Plans"),
to be drawn for the Expansion Space on Tenant's behalf:

          (a)  Complete Building Standard "Space Plans" (herein so called)
for the layout of the Expansion Space;

          (b)  Complete, finished and detailed 1/8 inch scale architectural
drawings and specifications for Tenant's partition layout, reflected ceiling,
telephone and electrical outlets, and finish schedule for the work to be done
by Landlord under Paragraph 3 hereof (the "Construction Plans"); and

          (c)  Complete Building Standard mechanical plans and specifications
where necessary for installation of normal air conditioning system and duct
work and heating and electrical facilities for the work to be done by Landlord
under Paragraph 3 hereof (the "MP & E Plans").

     Tenant shall pay all costs of preparing the Final Plans, subject, however,
to the reimbursement provisions of Paragraph 7 below.

     2.   Preparation of Final Plans; Changes to Final Plans. Tenant covenants
and agrees to furnish to Landlord all information necessary for the preparation
of each of the Space Plans, the Construction Plans and the M P & E Plans on or
before May 5, 1998. Landlord will cause the Space Plans, the Construction
Plans, and the M P & E Plans to be prepared from such information and will
submit such plans to Tenant. Within ten (10) days after receipt thereof, Tenant
shall approve the Space Plans, Construction Plans and M P & E Plans or indicate
what changes, if any, that it desires to make. Such proposed changes, if any,
shall be submitted to Landlord in writing for Landlord's written approval. If
within ten (10) days after receipt thereof, Tenant fails to approve any of the
Space Plans, Construction Plans and M P & E Plans or if Tenant fails to propose
in writing any changes to be made to such Space Plans, Construction Plans and M
P & E Plans, then Tenant shall be deemed to have approved each of same. Any
redrawing of all or any of the Final Plans occasioned by Tenant after Tenant's
approval (or deemed approval) thereof as well as any changes requested by
Tenant in connection with its initial review of the Final Plans which are
agreed to by Landlord shall be at Tenant's sole cost and expense and no portion
of the Credit (as defined in Paragraph 7 below) shall be applicable to such
costs.

     3.   Construction of Improvements. Subject to each of Paragraph 2 and
Paragraph 28 of the Lease, provided that Tenant has not committed an event of
default pursuant to Paragraph 20 of the Lease, Landlord agrees to cause the
improvements to the Expansion Space to be constructed pursuant to and in
substantial accordance with the Final Plans. The construction of such
improvements in the Expansion Space shall be at Tenant's sole cost and expense,
subject, however, to the reimbursement provisions of Paragraph 7 below. Tenant
acknowledges that all work done in the Expansion Space pursuant to this Work
Letter Agreement shall be performed by a contractor (and such subcontractors,
suppliers and laborers) designated by Landlord and approved by Tenant.

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     4.   Condition of Expansion Space. Landlord will, at Landlord's sole cost
and expense, construct all improvements to the Expansion Space necessary to
characterize the Expansion Space as being in Shell Condition (hereinafter
defined). As used herein the term "Shell Condition" means:

          (a)  The sprinkler system and sprinkler heads have been installed.

          (b)  The main ducting for the HVAC system has been installed.

          (c)  Electric lines have been run to junction boxes in the Expansion
               Space.

          (d)  The ceiling grid has been installed. Building standard ceiling
               tile and lights stacked on the floor.

          (e)  Smooth concrete floor slab.

     5.   Modifications to Shall Condition. To the extent that the Final Plans
call for any modifications (herein "Shell Modifications") to the Shell
Condition, the costs of such Shell Modifications shall be borne solely by
Tenant, subject, however, to the reimbursement provisions of Paragraph 7 below.
By way of example, and not by way of limitation, the following shall each be
examples of Shell Modifications:

          (a)  Any modifications to the existing sprinkler system, or the
moving of existing sprinkler heads, or the installation of additional sprinkler
heads.

          (b)  Any modifications to the existing HVAC system, the moving of
the existing ductwork and/or diffusers, or the installation of additional
ductwork and/or diffusers.

          (c)  Any rewiring of existing junction boxes, relocation of existing
junction boxes, or installation of additional junction boxes.

     6.   Building Standard. Tenant shall be required to use, and the Final
Plans shall specify Building Standard (a) light fixtures, (b) doors, (c)
ceiling tiles, and (d) hardware throughout the Expansion Space and the costs of
purchasing, transporting and installing each of the foregoing Building Standard
items shall be borne solely by Tenant, subject, however, to the reimbursement
provisions of Paragraph 7 below. Whenever the term "Building Standard" is
used in this Work Letter Agreement, it shall mean the exclusive type, brand,
quality, and/or quantity of materials Landlord designates from time to time to
be the quality or quantity to be used in the Building.

     7.   Payment of Costs: Credit. Tenant agrees to pay Landlord, promptly upon
being billed therefor, the actual cost (labor, materials, architectural, space
planning, engineering and other costs) of all work performed pursuant to this
Work Letter Agreement; Landlord shall have the right to submit interim
statements of cost incurred which shall be promptly paid by Tenant to Landlord.
Tenant agrees that all payments due to Landlord pursuant hereto shall
constitute payments of additional rent and that in the event of default of
payment thereof, Landlord shall (in addition to all other remedies) have the
same rights as in the event of default of payment of rent under the Lease.
Notwithstanding the above, so long as no event of default, as defined in
Paragraph 20 of the Lease, shall have occurred, Landlord shall credit Tenant
in an amount not to exceed $15.00 per square foot of Rentable Area in the
Expansion Space (the "Credit"), such Credit to be applied only against
sums due from Tenant to Landlord pursuant to this Work Letter Agreement
(exclusive of those sums which, pursuant to Paragraph 2 above are not eligible
to be offset by the Credit).

     8.   Delays. If Landlord shall be delayed in substantially completing the
work to be performed by Landlord pursuant to this Work Letter Agreement as a
result of:

          (a)  Tenant's failure to timely furnish information or specifications
in accordance with Paragraph 2 above; or

          (b)  Tenant's request for materials, finishes or installations other
than Landlord's Building Standard; or

          (c)  Tenant's changes in or modifications to any plans and
specifications or any of the Final Plans; or

          (d)  The performance of any work in the Expansion Space by a person,
firm or corporation employed by Tenant; (all such persons, firms or
corporations being subject to the approval of Landlord);

Tenant's obligation for payment of rental under the Second Amendment (as
affected by such waiver) shall be accelerated by the number of days of such
delay.

     9.   Entry by Tenant's Agents. Landlord will permit Tenant and its agents
to enter the Expansion Space prior to the date specified for the commencement
of Tenant's occupancy under the Second Amendment, in order that Tenant may
perform through its own contractors (to be first approved by Landlord) such
other work and decorations as Landlord may approve at the same time that
Landlord's contractors are working in the Expansion Space. The foregoing
license to enter, however, is conditioned upon Tenant's workmen and mechanics
working in harmony and not interfering with the labor employed by Landlord,
Landlord's mechanics or contractors or by any other tenant or their
contractors. Such license is further conditioned upon workers' compensation and
public liability insurance for bodily injury and property damage, all in
amounts and with companies and on forms satisfactory to Landlord, being
provided and at all times maintained by Tenant's contractors engaged in the
performance of the work, and certificates of such insurance being furnished to
Landlord prior to proceeding with the work. If at any time such entry shall
cause disharmony or interference therewith, Landlord may withdraw this license
upon forty-eight (48) hours written notice to Tenant. Such entry conditions
shall be deemed to be under all of the terms, covenants, provisions and
conditions of the Lease. Landlord shall not be liable in any way for any
injury, loss or damage which may occur to any of Tenant's decorations or
installations, the same being solely at Tenant's risk, and Tenant shall hold
Landlord harmless from any claim, demand or action arising from activities of
Tenant's contractors, workmen or mechanics.

     If the foregoing correctly sets forth our understanding, kindly
acknowledge your approval in the space provided below whereupon this work
letter shall become a binding agreement between us.

                                Yours very truly,

                                COLLINS CAMPBELL JOINT VENTURE
                                  a Texas general partnership

                                By: Jaytex Properties, Ltd.,
                                      a Texas limited partnership

                                    By: JRS Management, Inc.,
                                          a Texas corporation

                                          By: /s/ W. T. Field
                                              ----------------------------
                                              W. T. Field, President

AGREED TO AND ACCEPTED
as of the 8th day of May, 1998.

telecom technologies, inc.
 a Texas corporation

By: /s/ Anousheh Ansari
    ---------------------
Name: Anousheh Ansari

Title: President

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