Document:

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                                        SUBLEASE

THIS SUBLEASE AGREEMENT MADE between 2-INFINITY.COM, INC., hereinafter known
as Sublessor, and LYNKTEL, INC., hereinafter known as Sublessee.

WITNESSETH THAT:  Sublessor does hereby sublease and sublet unto Sublessee
all that certain 4,700 square feet of space commonly known as 333 NORTH
HOUSTON PKWY. E, SUITE 870 in the City of HOUSTON, State of TEXAS to be used
or occupied only for general office purposes, including the conduct of a
loan, finance and/or insurance business, for the term of months beginning on
the

5th day of May, 2000, and ending on the

5th day of May, 2004, for a total rental of

FIVE THOUSAND FOUR HUNDRED AND NINETY-TWO DOLLARS AND 00/100

$5,492.00 lawful money of the United States of America, payable as follows:
$5,492.00 on the first day of MAY 2000, and a like amount on the first day
of each and every month during the term of this sublease;

said rent payable to:

2-Infinity.com, Inc.
4828 Loop Central Dr., First Floor
Houston, TX 77081

or to such other person as Sublessor may from time to time designate by
notice in writing. If the monthly rental payment is not received on or before
five (5) days following the due date, said rental payment shall be in default
and service charge of 10% of the defaulted payment may, at the option of
2-Infinity.com, Inc., become due and payable.

This sublease is granted and accepted upon the foregoing and upon the
following covenants and conditions and subject to all terms of the attached
master lease, and subject to the following restrictions, to all and every one
of which the parties consent, and each of the parties hereby expressly
covenants and agrees to keep, perform and observe all the terms, covenants
and conditions herein contained on their or its part to be kept, performed
and observed:

HEREINAFTER, THE WORDS LESSOR SHALL BE KNOWN AS SUBLESSOR, LESSEE AS
SUBLESSEE, LANDLORD AS SUBLANDLORD AND TENANT AS SUBTENANT.

FIRST:  The lessee shall well and truly pay to the Lessor the rental herein
reserved; without demand therefore, on the days and in the manner herein
prescribed for the payment thereof.

SECOND:  Lessee agrees to be responsible for and to relieve and hereby
relieves Lessor from all liability by reason of any damage or injury to any
person or thing which may arise from or be due to the use of the demised
premises, and agrees to keep in force such insurance, in limits acceptable to
Lessor, as covers such contingencies. Lessee agrees to be responsible for
plate glass, if any existing in the premises. Lessor shall carry fire
insurance coverage with loss payable to Lessor and Lessee as their interests
may appear.

THIRD:  Lessee agrees to keep the premises clean and in good order; to keep,
at its own expense, the inside of same in as good repair as they are now,
reasonable wear and tear, and damage by fire and/or other casualty excepted;
not to use the premises for any illegal, immoral or environmentally hazardous
purpose and to abide by such reasonable rules and regulations as Lessor may
from time to time promulgate to the tenants in writing. The Lessor shall, at
Lessor's expense, keep the roof and the outside walls of the building
containing the demised premises in good condition and repair and shall make
all structural repairs and maintain all electric wiring and plumbing.
Notwithstanding anything contained herein to the contrary, the lessee shall
be responsible for any and all repairs required as the result of the lessee's
failure to comply with various federal, state and local government statutes
and rules and regulations dealing with environmental hazards.

FOURTH:  The Lessee, at any time during the term, shall permit inspection of
the demised premises during reasonable hours by the Lessor or the Lessor's
agents or representatives, and by or on behalf of prospective purchasers, and
during the two (2) months next preceding the expiration of this lease, or any
renewal thereof, shall permit inspection thereof by and on behalf of the
prospective tenants. The Lessee shall permit, during the two (2) months next
preceding the expiration of this lease, or any renewal thereof, a sign or
notice indicating that the premises are to let or for sale to be posted and
remain upon the demised premises.

FIFTH:  On the last day of the term herein demised, or in the event that
Lessee has failed to correct within fifteen (15) days after registered
written notice to the demised premises, any breach of the covenants found
herein, Lessee shall peaceably and quietly leave, surrender and yield up unto
the Lessor all and singular the demised premises but, if this lease is
terminate because the Lessee has so breached the covenants found herein, or
has abandoned the premises, Lessor may immediately, or anytime thereafter,
re-enter and resume possession of said premises by a suitable action or
proceeding at law or equity, or by force, or otherwise, without being liable
for any damages therefore; and Lessor

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an amount equal to the amount of all rent reserved and unpaid under this
lease, less the net rent collected by the Lessor on reletting the demised
premises, said amount which shall be due and payable by the Lessee on the
several days on which the rent reserved in this lease would become due and
payable; that is to say, upon each of such days, the Lessee shall pay to the
Lessor the amount of deficiency then existing.

SIXTH:  Lessee hereby waives the benefits of all the laws exempting property,
of any amount of value, from levy and sale on execution of distress for rent
upon Lessor's warrant that may be issued, or upon any under this lease;
Lessee expressly waives to Lessor any provision of any law requiring notice
to vacate premises, prior to the end of the term, as a pre-requisite to the
maintaining of any action for the possession of the demised premises.

SEVENTH:  In the event the demised premises are totally destroyed by fire,
enemy action or other casualty, this lease shall absolutely cease and
terminate, and the rent shall abate for the balance of the term, except that
Lessee may have the first right of refusal to said premises if Lessor elects
to restore same during the term of this lease or any renewal thereof, if the
damage caused as above by only partial, the rent shall be abated to an extent
corresponding with the damage until repaired, all repairs shall be made with
reasonable dispatch and at such times as not to create unwarranted
interference with Lessee's business. Lessee shall not be liable to Lessor for
any damage to the premises within the coverage of the standard fire insurance
policy in use in the geographical area where the premises is located, whether
or not loss covered thereby is due to fault of Lessee.

EIGHT:  Lessee may make such repairs and alterations and decorations in and
to the leased premises, and the building thereon as it may deem desirable for
its use thereof, provided that if such repairs and alterations substantially
alter the basic structure of the building, or adversely affect the soundness
thereof or value thereof, the prior written consent of Lessor shall be
obtained before such work is commenced; upon termination of this Lease, or
any renewal thereof, Lessee may, at its own expense, remove its furniture,
fixtures, partitions and other such items as it has installed during the
term of this lease, or any renewal thereof, provided, however, the Lessee
shall repair any damage caused by such removal.

NINTH:  Lessee may place such signs upon the outside walls or within the
premises as it deems necessary, provided that any and all signs placed on the
within lease premises by Lessee shall be maintained in compliance with rules
and regulations governing such signs and Lessee shall be responsible to
Lessor for such damage caused by installation, use or maintenance of said
signs, and Lessee agrees upon removal of said signs to repair all damage
incident to such removal.

TENTH:  In and so long as the Lessee pays the rent reserved by this lease,
and performs and observes all of the covenants and provisions hereof, the
Lessee shall quietly enjoy the demised premises, subject, however, to the
terms of this lease. Lessor warrants that there does not exist, as of the
date hereof, any zoning restrictions prohibiting the use of the demised
premises as herein provided for.

ELEVENTH:  This instrument contains all of the agreements and conditions made
between the parties hereto and may not be modified orally or in any manner,
than by an agreement in writing signed by all the parties hereto, or their
respective successors in interest.

TWELFTH:  Lessee shall pay Lessor one month's rental as security deposit.
Said deposit is to be refunded after Lessee vacates demised premises and
sublease expires.

WITNESS our hands, this 5th day of May, 2000.

LESSOR:  AIR NEXUS/2-INFINITY.COM INC.

WITNESS:

/s/ Sharon Jackson
-----------------------------------------

BY:     /s/ Patrica C. Morgan
NAME:   PATRICA C. MORGAN
TITLE:  Chief Operating Officer

LESSEE:  LYNKTEL, INC.

WITNESS:  /s/ illegible

BY:     /s/ illegible
NAME:   Jonas E. McCane, Jr.
TITLE:  CEO

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                               CONSENT TO SUBLEASE

HARVARD PROPERTY (333 SAM HOUSTON), in that certain Lease Agreement dated
July 12, 1999, described in the attached Sublease does hereby give written
consent to the attached Sublease of AIR NEXUS/2-INFINITY.COM, INC., right,
title and interest in and to the Lease to LYNKTEL, INC.

Such consent to Sublease shall not relieve Overtenant from liability for
payment of Rent, additional rent, or from the obligations to keep and be
bounded by the terms, conditions and covenants of the Lease. This acceptance
of Rent from any other person shall not be deemed to be a waiver of any of
the provisions of the Lease or a consent to the assignment or subletting to
the leased premises.

LANDLORD:  HARVARD PROPERTY (333 SAM HOUSTON)

BY:     /s/ John Powers
        ---------------------------------
NAME:   John Powers
        ---------------------------------

TITLE:  SVP
        ---------------------------------

DATE:   5/31/00
        ---------------------------------<PAGE>

                         FIRST AMENDMENT TO LEASE AGREEMENT

       THIS FIRST AMENDMENT TO LEASE ("First Amendment") is made this 19TH
day of JANUARY, 2000, by and between THE REALITY ASSOCIATES FUND IV, L.P., a
Delaware limited partnership, successor in interest to Cigna Real Estate Fund
T, Limited Partnership ("Landlord") and LAKOTA TECHNOLOGIES, INC., a Colorado
corporation; successor in interest to Lakota Energy, Inc. ("Tenant").

                                 W I T N E S S E T H:

       WHEREAS, Cigna Real Estate Fund T, Limited Partnership, Landlord's
immediate predecessor in interest, and Lakota Energy, Inc., Tenant's
immediate predecessor in interest, entered into that certain Lease dated
December 17, 1996 (the "Lease"), pursuant to which Tenant leased that certain
premises in Overlook I (the "Project"), 2849 Paces Ferry Road, Atlanta,
Georgia 30339, said premises containing One Thousand Two Hundred Seventy
Eight (1,278) rentable square feet of space (the "Premises");

       WHEREAS, Landlord and Tenant desire to amend the Lease to extend the
term and to amend certain other terms and conditions of the Lease as herein
provided.

       NOW, THEREFORE, in consideration of the premises and mutual covenants
and agreements herein contained and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
Landlord and Tenant hereby agree to the following:

       1.    RECITALS.  The recitals set forth above are incorporated herein
by this reference with the same force and effect as if fully set forth
hereinafter.

       2.    CAPITALIZED TERMS.  Capitalized terms not otherwise defined
herein shall have the meaning ascribed to them in the Lease.

       3.    LANDLORD.  All references in the Lease to Cigna Real Estate Fund
T as Landlord shall hereinafter to the Realty Associates Fund IV, L.P. which
acquired the Project.

       4.    TENANT.  All references in the Lease to Lakota Energy, Inc. as
Tenant shall hereinafter refer to Lakota Technologies, Inc.

       5.    TERM.  The Term of the Lease is hereby extended for three (3)
years commencing on January 15, 2000 (the "Renewal Date") and expiring
January 31, 2003 (the "Termination Date") (inclusively, the "Renewal Term")
unless sooner terminated pursuant to any provision of the Lease or hereof.

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       6.    BASE RENTAL.  Notwithstanding anything to the contrary in the
Lease, during the Renewal Term, Tenant shall pay Base Rental for the entire
Premises to Landlord in the manner and at the times set forth in Section 5(a)
of the Lease, according to the following schedule:

<TABLE>
<CAPTION>

                                   Annual                 Monthly
        Lease Period               Base Rental            Base Rental
        ------------               -----------            -----------
        <S>                        <C>                    <C>
        01/15/00-01/14/01          $25,560.00             $2,130.00
        01/15/01-01/14/02          $26,326.80             $2,193.90
        01/15/02-01/31/03          $27,116.64             $2,259.72
</TABLE>

        7.    NOTICES.  Paragraph 23 of the Lease is hereby deleted in its
entirety and the following Paragraph 23 substituted in lieu thereof:

              "NOTICES: 23. Any notice required or permitted to be given
        hereunder shall be in writing and may be given by certified mail,
        return receipt requested, personal delivery, Federal Express or other
        delivery service. If notice is given by certified mail, return
        receipt requested, notice shall be deemed given three (3) days after the
        notice is deposited with the U.S. Mail, postage prepaid, addressed to
        Tenant or to Landlord at the address set forth below. If notice is given
        by personal delivery, Federal Express or other delivery service, notice
        shall be deemed given on the date the notice is actually received by
        Landlord or Tenant. Either party may by notice to the other specify a
        different address for notice purposes. Notwithstanding the address set
        forth below for Tenant, upon Tenant's taking possession of the Premises,
        the Premises shall constitute Tenant's address for notice purposes. A
        copy of all notices required or permitted to be given to Landlord
        hereunder shall be concurrently transmitted to such party or parties at
        such addresses as Landlord may from time to time designate by notice to
        Tenant.

        To Landlord at:         The Realty Associates Fund IV, L.P.
                                c/o Trammell Crow Company
                                Five Concourse Parkway, Suite 1600
                                Atlanta, Georgia 30328

        With a Copy to:         TA Associates Realty
                                28 State Street
                                Boston, MA 02109
                                Attention: Ms. Pamela Adamian

        8.    HAZARDOUS MATERIAL.  Section 7 of the of the Lease is hereby
modified by adding the following at the end of Section 7:

              "For purposes of this Lease, the term "Hazardous Materials"
shall also mean any hazardous substance, hazardous waste, infectious waste,
or toxic substance, material, or waste which becomes regulated or is defined
as such by any local, state or federal governmental authority. Except for
small quantities of ordinary office supplies such as copier toners, liquid
paper, glue, ink and common household cleaning materials, Tenant shall not
cause or permit any Hazardous Material to be brought, kept or used in or
about the Premises or the Building by Tenant, its agents or employees. Tenant
hereby agrees to indemnify Landlord from and against any breach by Tenant of
the obligations stated in the preceding sentence, and agrees to defend and
hold Landlord harmless from and against any and all claims, judgments,
damages, penalties, fines, costs, liabilities, or losses (including,

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without limitation, diminution in value of the Building, damages for the loss
or restriction of use of rentable space or of any amenity of the Building,
damages arising from any adverse impact on marketing of space in the
Building, sums paid in settlement of claims, attorneys' fees, consultant fees
and expert fees) which arise during or after the term of the Lease (as the
same may be extended) as a result of such breach. This indemnification of
Landlord by Tenant includes, without limitation, costs incurred in connection
with any investigation of site conditions and any cleanup, remedial removal,
or restoration work required due to the presence of Hazardous Material caused
by Tenant, its agents or employees. Tenant shall promptly notify Landlord of
any release of a Hazardous Material in the premises or at the Building of
which Tenant becomes aware, whether caused by Tenant or any other person or
entity. The provisions of this Section 7 shall survive the termination of the
Lease."

      9.   COMPLIANCE WITH LAWS.  The Lease is hereby modified by adding the
following Section 38:

           "38.  To the extent that the Landlord receives any notice from a
      governmental entity that the Building is not in compliance with the
      Americans with Disabilities Act ("ADA") and the Landlord is obligated
      pursuant to a final determination to undertake action in order to
      comply with ADA, then in such event Landlord agrees to undertake such
      remedial action at Landlord's sole cost and expense. To the extent that
      such notice requires action with regard solely to Tenant's particular
      use of the Premises, Tenant shall be obligated to undertake such action
      at Tenant's sole cost and expense."

      10.  TENANT IMPROVEMENTS.

           a.   Tenant hereby acknowledges that all obligations of Landlord
pursuant to Exhibit C and Exhibit E to the Lease have been met.

           b.   Landlord, at Landlord's sole cost and expense, shall touch-up
the Premises with paint where needed provided the cost of such re-painting
shall not exceed One and 00/100 Dollar per rentable spare foot of space in
the Premises. Except as provided in this Paragraph 10, Landlord shall have
no further obligation to make any improvements to the Premises on behalf of
Tenant.

      11.  BROKER.  Tenant represents and warrants to Landlord that Tenant
has not had any dealings or entered into any agreements with any person,
entity, realtor, broker, agent or finder in connection with the negotiation of
this First Amendment other than Trammell Crow Company. Tenant shall indemnify
and hold Landlord harmless from and against any loss, claim, damage, expense
(including costs of suit and reasonable attorneys' fees) or liability for any
compensation, commission or charges claimed by any other realtor, broker,
agent or finder claiming to have dealt with Tenant in connection with this
First Amendment.

      12.  REAFFIRMATION OF TERMS.  Except as modified herein, all of the
terms, covenants and provisions of the Lease are hereby confirmed and
ratified and shall remain unchanged and in full force and effect.

      13.  REPRESENTATIONS.  Tenant hereby represents and warrants to
Landlord that Tenant (i) is not in default of any of its obligations under
the Lease and that such Lease is valid, binding and enforceable in accordance
with its terms, (ii) has full power and authority to execute and perform this
First Amendment, and (iii) has taken all action necessary to authorize the
execution and performance of this First Amendment.

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      14.  COUNTERPART COPIES.  This First Amendment may be executed in two
or more counterpart copies, each of which shall be deemed to be an original
and all of which counterparts shall have the same force and effect as if the
parties hereto had executed a single copy of this First Amendment.

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

                                    LANDLORD

                                    The Realty Associates Fund IV, L.P.,
                                    a Delaware limited partnership

                                    By:  Realty Associates Fund IV LLC,
                                         a Massachusetts limited liability
                                         company, general partner

                                         By:  Realty Associates Advisors LLC,
                                              a Delaware limited liability
                                              company, Manager

                                              By:  Realty Associates Advisors
                                                   Trust, a Massachusetts
                                                   business trust, sole member

                                                   By: /s/ Janene P. Behler
                                                       --------------------

                                    By:  Realty Associates Fund IV Texas
                                         Corporation, A Texas corporation,
                                         general partner

                                         By: /s/ Janene P. Behler
                                             --------------------

                                    TENANT:  JANENE P. BEHLER
                                             REGIONAL DIRECTOR

                                    Lakota Technologies, Inc., a Colorado
                                    corporation

                                    By:  /s/ [illegible]
                                         --------------------------------

                                    Its: President
                                         --------------------------------

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