Document:

<PAGE>   1
                                                                    EXHIBIT 10.4

                                                                   TDS AGREEMENT
                                                                  EXECUTION COPY

                               TDS STOCKHOLDERS AGREEMENT

                  This TDS Stockholders Agreement (this "Agreement") dated as of
August 26, 2000 among Powertel, Inc., a Delaware corporation ("Powertel") and
the stockholder of VoiceStream listed on the signature page hereto
("Stockholder").

                  WHEREAS, simultaneously with the execution of this Agreement,
VoiceStream Wireless Corporation, a Delaware corporation ("VoiceStream") and
Powertel are entering into an Agreement and Plan of Merger (the "Powertel Merger
Agreement"), dated as of the date hereof, providing, among other things, for the
merger of a subsidiary of VoiceStream with and into Powertel (the "Merger");

                  WHEREAS, Powertel has agreed to enter into the Powertel Merger
Agreement only if the VoiceStream Principal Stockholders enter into a
VoiceStream Voting Agreement, including this Agreement;

                  WHEREAS, in the Powertel Merger Agreement VoiceStream has
agreed, subject to the conditions set forth therein, to acquire all of the
shares of Powertel Common Stock (as defined below);

                  NOW THEREFORE, in consideration of the foregoing and the
mutual premises, representations, warranties, covenants and agreements contained
herein and in the Merger Agreement, the parties hereto, intending to be legally
bound hereby, except as set forth in the Side Agreement between Stockholder and
Powertel dated the date hereof (the "Side Agreement"), agree as follows:

                  1.       Certain Definitions.

                  This Agreement is one of the VoiceStream Voting Agreements
referenced in the recitals to the Powertel Merger Agreement. For the purposes of
this Agreement, all capitalized terms used but not otherwise defined herein
shall have the respective meanings given to such terms in the Powertel Merger
Agreement.

                  For the purposes of this Agreement, the words "beneficially
owned" or "beneficial ownership" shall include, with respect to any securities,
the beneficial ownership by Stockholder and by any direct or indirect Subsidiary
of Stockholder.

                  "Transfer" means, with respect to any security, the sale,
transfer, pledge, hypothecation, encumbrance, assignment or other disposition of
such security or the record or beneficial ownership thereof, the offer to make
such a sale, transfer or other disposition, and each agreement, arrangement or
understanding, whether or not in writing, to effect any of the foregoing.

                  2.       Representations; Warranties and Covenants of
Stockholder. Stockholder hereby represents and warrants to Powertel as follows:

<PAGE>   2

                  (a)      Title. As of the date hereof, Stockholder is the sole
record or beneficial owner of the number of shares of VoiceStream Common Stock
or VoiceStream preferred stock, as the case may be, set forth opposite
Stockholder's name on Exhibit A attached hereto (the "Existing Shares" and,
together with record or beneficial ownership of any shares of VoiceStream Common
Stock or other voting capital stock of VoiceStream acquired after the date
hereof, whether upon the exercise of warrants or options, conversion of
VoiceStream preferred stock or any convertible securities or otherwise,
Stockholder's "Shares"), and/or the number of warrants, options or other rights
to acquire or receive such VoiceStream Common Stock or VoiceStream preferred
stock, as the case may be, set forth opposite such Stockholder's name on Exhibit
A attached hereto (the "Existing Rights" and, together with record or beneficial
ownership of any warrants, options or other rights to acquire or receive such
shares of VoiceStream Common Stock or other voting capital stock of VoiceStream
acquired after the date hereof, Stockholder's "Rights"). Stockholder is the
lawful owner of the Existing Shares and Existing Rights, free and clear of all
liens, claims, charges, security interests or other encumbrances, except as
disclosed on Exhibit A. As of the date hereof, the Existing Shares constitute
all of the capital stock of VoiceStream owned of record or beneficially by
Stockholder (excluding the Existing Rights) and Stockholder does not own of
record or beneficially, or have the right to acquire (whether currently, upon
lapse of time, following the satisfaction of any conditions, upon the occurrence
of any event or any combination of the foregoing) any shares of VoiceStream
Common Stock or VoiceStream preferred stock or any other securities convertible
into or exchangeable or exercisable for shares of VoiceStream Common Stock,
except pursuant to the Existing Rights.

                  (b)      Right to Vote. Except as disclosed on Exhibit A,
Stockholder has, and (subject to the provisions of Section 3(a)) will have at
the VoiceStream Stockholders' Meeting, with respect to all of Stockholder's
Shares listed on Exhibit A and acquired subsequent to the date hereof and prior
to the record date for the VoiceStream Stockholders' Meeting, sole voting power,
sole power of disposition or sole power to issue instructions with respect to
the matters set forth in Section 4 hereof and to fulfill its obligations under
such Section and shall not take any action or grant any person any proxy
(revocable or irrevocable) or power-of-attorney with respect to any Shares or
Rights inconsistent with his or its obligations as provided by Section 4 and
Section 5 hereof. Stockholder hereby revokes any and all proxies with respect to
Stockholder's Existing Shares to the extent they are inconsistent with
Stockholder's obligations under this Agreement.

                  (c)      Authority. Stockholder has full legal power,
authority, legal capacity and right to execute and deliver, and to perform its
or his obligations under, this Agreement. No proceedings or actions on the part
of Stockholder other than those already taken are necessary to authorize the
execution, delivery or performance of this Agreement or the consummation of the
transactions contemplated hereby. This Agreement has been duly and validly
executed and delivered by Stockholder and constitutes a valid and binding
agreement of such Stockholder enforceable against Stockholder in accordance with
its terms, subject to (i) bankruptcy, insolvency, moratorium and other similar
laws now or hereafter in effect relating to or affecting creditors rights
generally and (ii) general principles of equity (regardless of whether
considered in a proceeding at law or in equity).

                                       2
<PAGE>   3

                  (d)      Conflicting Instruments. Neither the execution and
delivery of this Agreement nor the performance by Stockholder of its agreements
and obligations hereunder will result in any breach or violation of, or be in
conflict with or constitute a default under, any term of any agreement,
judgment, injunction, order, decree, federal law or regulation to which
Stockholder is a party or by which Stockholder (or any of its assets) is bound.

                  (e)      Powertel's Reliance. Stockholder understands and
acknowledges that Powertel is entering into the Powertel Merger Agreement in
reliance upon Stockholder's execution, delivery and performance of this
Agreement.

                  3.       Restriction on Transfer; Other Restrictions.

                  (a)      From the date hereof until the later of January 1,
2001 and the date of the VoiceStream Stockholders' Meeting, Stockholder agrees
not to Transfer any Shares or Rights owned of record or beneficially by
Stockholder, except as otherwise permitted by this Section 3 or pursuant to the
Powertel Merger Agreement or the DT Merger Agreement (including the Stockholder
Agreements entered into in connection therewith), Transfers to any Affiliate of
the Stockholder who agrees in writing to be bound by the terms of this Agreement
or Transfers which occur by operation of law if the transferee remains, or
agrees in writing to remain, bound by the terms of this Agreement, other than,
in each case, with Powertel's prior written consent, provided, however, that
this Section 3(a) shall cease to be of any force or effect immediately upon
termination of the Powertel Merger Agreement.

                  (b)      Stockholder agrees that if at any time during the
period beginning on the later of January 1, 2001 and the date of the VoiceStream
Stockholders' Meeting and continuing until the first to occur of (1) the
Effective Time and (2) the termination of the Powertel Merger Agreement,
Stockholder proposes to Transfer, or exercise or propose to exercise
registration rights with respect to, more than 25% of the Stockholders' Shares
(individually or in the aggregate with other Transfers made during such period),
Stockholder will notify the Powertel stockholders listed on Exhibit B attached
hereto (the "Powertel Stockholders") in writing at the addresses set forth on
Exhibit B at least three Business Days in advance of such proposed Transfer or
exercise of rights, whichever is first to occur, and shall waive any right of
Stockholder to preclude or delay the filing of a registration statement or a
Transfer by the Powertel Stockholders with respect to Powertel Stock up to the
amounts permitted under Section 3.3 of such Powertel Stockholders' Powertel
Stockholders Agreements with VoiceStream (as such amounts may be increased by
the provisions of such Section 3.3).

                  (c)      Stockholder agrees that if at any time during the
period beginning on the Effective Time through and including the six (6) month
anniversary of the Effective Time, Stockholder proposes to Transfer, or exercise
or propose to exercise registration rights with respect to more than such number
of Shares that Stockholder is permitted to Transfer under Rule 144 promulgated
under the Securities Act, including the volume restriction contained therein
(individually or in the aggregate with other Transfers made during such period),
Stockholder will notify the Powertel Stockholders in writing at least three
Business Days in advance of such proposed Transfer or exercise of rights,
whichever is first to occur, and, at Stockholder's option, either (i) allow each
Powertel Stockholder to include a proportionate percentage (i.e., a percentage
equivalent to the ratio of the total number of Shares offered for sale by the

                                       3
<PAGE>   4

Stockholders to the total number of Shares beneficially owned by the
Stockholders) of the total number of shares of VoiceStream Common Stock
beneficially owned by such Powertel Stockholder in any registration statement
requested to be filed by the Stockholders or (ii) shall waive any right that
Stockholder may have to preclude or delay the filing of a registration statement
by any of the Powertel Stockholders covering a number of shares up to that
permitted under Section 3.4 of such Powertel Stockholders' Powertel Stockholders
Agreements with VoiceStream (as such number may be increased by the provisions
of such Section 3.4).

                  4.       Agreement to Vote. Stockholder hereby irrevocably and
unconditionally agrees to vote or to cause to be voted or provide a consent with
respect to, all Shares that he, she or it owns of record or beneficially as of
the record date for the VoiceStream Stockholders' Meeting at the VoiceStream
Stockholders' Meeting and at any other annual or special meeting of stockholders
of VoiceStream or action by written consent where such matters arise in favor of
the Powertel Merger Agreement and, if required, the other transactions
referenced in the Powertel Merger Agreement, and against the liquidation or
winding up of VoiceStream.

                  5.       Delivery of Proxy. In furtherance of the agreements
contained in Section 4 hereof, Stockholder hereby agrees (a) to complete and
send the proxy card received by such Stockholder with the Joint Proxy Statement,
so that such proxy card is received by VoiceStream, as prescribed by the Joint
Proxy Statement, not later than the fifth Business Day preceding the day of the
VoiceStream Stockholders Meeting, (b) to vote, by completing such proxy card but
not otherwise, all the Shares he, she or it owns of record or beneficially as of
the record date for the VoiceStream Stockholder' Meeting (i) in favor of the
Powertel Merger Agreement and, if required, the other transactions referenced in
the Powertel Merger Agreement and (ii) if the opportunity to do so is presented
to Stockholder on the proxy card, against the liquidation or winding up of
VoiceStream and (c) not to revoke any such proxy.

                  6.       Amendment of Existing Voting Agreements. Stockholder
and certain other stockholders of VoiceStream are parties to a Voting Agreement
dated February 25, 2000 (as amended May 4, 2000), and a certain First Amended
and Restated Voting Agreement dated July 23, 2000 which will take effect in
accordance with its terms (collectively the "Existing Voting Agreements")
pursuant to which they have agreed to vote all shares of VoiceStream Common
Stock and VoiceStream preferred stock beneficially owned by each of them at the
time of such vote in the election of directors in accordance with the procedures
and provisions set forth in such agreements. On or before the Effective Time,
provided that the Stockholder is still subject to the Existing Voting
Agreements, Stockholder agrees to execute and deliver, and VoiceStream agrees
that it will make commercially reasonable efforts to cause the other parties to
the Existing Voting Agreements to execute and deliver, an amendment to the
Existing Voting Agreements (the "Amended Voting Agreement") on terms mutually
satisfactory to VoiceStream, Stockholder, the Powertel Principal Stockholders
(who will become parties to the Amended Voting Agreement), and the other parties
who are presently parties to the Existing Voting Agreements, providing for: (i)
the nomination of one representative of the Powertel stockholders to the
VoiceStream Board of Directors who shall be initially designated by the Powertel
Board of Directors and who shall also be reasonably satisfactory to VoiceStream;
(ii) the creation of a vacancy on the VoiceStream Board of Directors (and the
approval of any Bylaw amendments or other actions required to do so); (iii) the
appointment of such nominee (and any successor nominee) to a newly created
vacancy on the VoiceStream Board of Directors; and (iv) an

                                       4
<PAGE>   5

agreement to vote all shares of VoiceStream Common Stock and other voting
securities of VoiceStream (and all securities received in exchange, replacement
or substitution therefore, or as a dividend or result of a stock split with
respect thereto) owned of record or beneficially by the Stockholder at the time
of such vote for such nominee (and any successor nominee) at the first two
annual meetings after the Effective Time. If VoiceStream, Stockholder and the
other parties to the Existing Voting Agreements are unable to cause the
execution of an Amended Voting Agreement, Stockholder agrees to execute a
separate voting agreement with the Powertel Principal Stockholders and such
other VoiceStream stockholders who agree to enter into such separate voting
agreement on terms and conditions substantially similar to the Existing Voting
Agreements making the same additional provisions as set forth in the preceding
sentence. Prior to the Effective Time, the Powertel Board of Directors may make
such provisions as it deems appropriate for successor nominees each of which
shall be reasonably satisfactory to VoiceStream. After the Effective Time, any
nominee or successor nominee shall be selected by mutual agreement of ITC
Holding Company, Inc., a Delaware corporation ("ITCORP") and SCANA
Communications Holdings, Inc., a Delaware corporation ("SCORP") or, if no such
agreement can be reached, by whichever of ITCORP and SCORP beneficially owns the
larger number of shares of VoiceStream Common Stock and VoiceStream preferred
stock (on an as-if-converted basis).

                  7.       Additional Shares and Additional Rights. If, after
the date hereof, Stockholder acquires record or beneficial ownership of any
additional shares of capital stock of VoiceStream (any such shares, "Additional
Shares"), including, without limitation, upon exercise of any option, warrant or
right to acquire shares of capital stock of VoiceStream, through the conversion
of the VoiceStream preferred stock or through any stock dividend or stock split
(any such options, warrants or rights, "Additional Rights"), the provisions of
this Agreement applicable to the Shares shall be applicable to such Additional
Shares and Additional Rights from and after the date of acquisition thereof. The
provisions of the immediately preceding sentence shall be effective with respect
to Additional Shares without action by any Person immediately upon the
acquisition by Stockholder of record or beneficial ownership of such Additional
Shares or Additional Rights.

                  8.       Miscellaneous.

                  (a)      Entire Agreement. This Agreement constitutes the
entire agreement among the parties with respect to the subject matter hereof.

                  (b)      Costs and Expenses. All costs and expenses incurred
in connection with this Agreement and the transactions contemplated hereby shall
be paid by the party incurring such expenses.

                  (c)      Invalid Provisions. If any provision of this
Agreement shall be invalid or unenforceable under applicable law, such provision
shall be ineffective to the extent of such invalidity or unenforceability only,
without it affecting the remaining provisions of this Agreement.

                                       5
<PAGE>   6

                  (d)      Execution in Counterparts. This Agreement may be
executed in counterparts transmitted and delivered by facsimile each of which
shall be an original with the same effect as if the signatures hereto and
thereto were upon the same instrument.

                  (e)      Specific Performance. Stockholder agrees with
Powertel as to himself or itself that if for any reason Stockholder fails to
perform any of his or its agreements or obligations under this Agreement,
irreparable harm or injury to Powertel would be caused as to which money damages
would not be an adequate remedy. Accordingly, Stockholder agrees that, in
seeking to enforce this Agreement against Stockholder, Powertel shall be
entitled, in addition to any other remedy available at law, equity or otherwise,
to specific performance and injunctive and other equitable relief. The
provisions of this Section 8(e) are without prejudice to any other rights or
remedies, whether at law or in equity, that Powertel may have against
Stockholder for any failure to perform any of its agreements or obligations
under this Agreement.

                  (f)      Amendments; Termination.

                           (i)      This Agreement, including this Section 8(f),
         may not be modified, amended, altered or supplemented, except upon the
         execution and delivery of a written agreement executed by the parties
         hereto.

                           (ii)     The provisions of this Agreement (other than
         Sections 3, 4 and 6) shall terminate upon the earliest to occur of (A)
         the consummation of the Merger, (B) the date that is two (2) years
         after the date hereof, and (C) the termination of the Merger Agreement.
         The provisions of Sections 3(a), 3(b) and 4 of this Agreement shall
         terminate when the applicable time periods set forth in Section 3
         lapse, and the provisions of Section 3(c) shall terminate on the
         earlier of the six (6) month anniversary of the Effective Time or upon
         the termination of the Powertel Merger Agreement. The provisions of
         Section 6 shall terminate upon earlier of the execution and delivery of
         a new or amended voting agreement or the termination of the Powertel
         Merger Agreement.

                  (g)      Governing Law; Submission and Jurisdiction.

                           (i)      This Agreement shall be governed by and
         construed in accordance with the laws of the State of Delaware without
         giving effect to the principles of conflicts of laws thereof.

                           (ii)     Each of the parties hereto irrevocably
         agrees that any legal action or proceeding with respect to this
         Agreement or for recognition and enforcement of any judgment in respect
         hereof brought by the other party hereto or its successors or assigns
         shall be brought and determined only in the United States District
         Court for the State of Delaware or, in the event (but only in the
         event) that such court does not have subject matter jurisdiction over
         such action or proceeding, in the courts of the State of Delaware. Each
         of the parties hereto hereby irrevocable submits with regard to any
         such action or proceeding for itself and in respect to its property,
         generally and unconditionally, to the personal jurisdiction of the
         aforesaid courts. Each of the parties hereto hereby irrevocably waives,
         and agrees not to assert, by way of motion, as a defense, counterclaim
         or otherwise, in any action or proceeding with respect to this
         Agreement,

                                       6
<PAGE>   7

         (A) any claim that it is not personally subject to the jurisdiction of
         the above-named courts for any reason other than the failure to serve
         in accordance with this Section 8(g)(ii) or that it or its property is
         exempt or immune from jurisdiction of any such court or from any legal
         process commenced in such courts (whether through service of notice,
         attachment prior to judgment, attachment in aid of execution of
         judgment, execution of judgment or otherwise), and (B) to the fullest
         extent permitted by the applicable law, that (x) the suit, action or
         proceeding in such court is brought in an inconvenient forum, (y) the
         venue of such suit, action or proceeding is improper and (z) this
         Agreement, or the subject matter hereof, may not be enforced in or by
         such courts. Without limiting the foregoing, each party agrees that
         service of process on such party as provided in Section 8(i) shall be
         deemed effective service of process on such party.

                  (h)      Successors and Assigns. The provisions of this
Agreement shall be binding upon and inure to the benefit of the parties hereto
and their respective legal successors (including, in the case of Stockholder or
any other individual, any executors, administrators, estates, legal
representatives and heirs of Stockholder or such individual) and permitted
assigns; provided that, except as otherwise provided in this Agreement, no party
may assign, delegate or otherwise transfer any of its rights or obligations
under this Agreement.

                  (i)      Notices. All notices and other communications given
or made pursuant hereto shall be in writing and shall be deemed to have been
duly given or made as of the date of receipt and shall be delivered personally
or sent by overnight courier or sent by telecopy, to the Parties at the
following addresses or telecopy numbers (or at such other address or telecopy
number for a party as shall be specified by like notice):

                           (i)      if to Stockholder, at Stockholder's address
appearing on Exhibit A hereto or at any other address that Stockholder may have
provided in writing to Powertel,

                           with a copy to:

                                    Preston Gates & Ellis LLP
                                    701 Fifth Avenue, Suite 5000
                                    Seattle, WA  98104
                                    Attn:  Richard B. Dodd, Esq.
                                    Telecopy No: 206-623-7022

                           And a copy to:

                                    Friedman, Kaplan & Seiler LLP
                                    875 Third Avenue
                                    New York, New York  10022
                                    Attention: Barry A. Adelman
                                    Facsimile: 212-355-6401

                           (ii)     if to Powertel:

                                    Powertel, Inc.

                                       7
<PAGE>   8

                                    1239 O.G. Skinner Drive
                                    West Point, GA  31833
                                    Attention: Chairman of the Board
                                    Facsimile: 706-645-9563

                           with a copy to:

                                    Morris Manning & Martin, L.L.P.
                                    1600 Atlanta Financial Center
                                    3343 Peachtree Road, NE
                                    Atlanta, Georgia  30326
                                    Attention: James Walker IV
                                    Facsimile: 404-365-9532

                  (j)      Third Party Beneficiaries. This Agreement is entered
into solely for the benefit of the parties hereto and no person other than such
parties, and their respective successors and permitted assigns to the extent
expressly provided herein, may exercise any right or enforce any obligation
hereunder; provided, however, that the Powertel Stockholders shall be deemed to
be third party beneficiaries of this Agreement solely with respect to the
notification provisions contained in Sections 3(b) and 3(c) hereof.

                                       8
<PAGE>   9

                       STOCKHOLDERS SIGNATURE PAGE -- TDS

         IN WITNESS WHEREOF, the parties hereto have executed this TDS
Stockholders Agreement as of this 26th day of August, 2000.

                                             POWERTEL, INC.

                                             By: /s/ ALLEN E. SMITH
                                                --------------------------------
                                                Name: Allen E. Smith
                                                Title: President and Chief
                                                       Executive Officer

                                             TELEPHONE AND DATA SYSTEMS,
                                               INC.

                                             By: /s/ SANDRA L. HELTON
                                                --------------------------------
                                                Name: Sandra L. Helton
                                                Title: Executive Vice President,
                                                       Finance and CEO

                                       9
<PAGE>   10

         VoiceStream Wireless Corporation hereby agrees with Powertel, Inc. that
it agrees to comply with the provisions of Section 6 of the TDS Stockholder
Agreement dated August 26, 2000 between Powertel, Inc. and Telephone and Data
Systems, Inc.

                                           VOICESTREAM WIRELESS
                                             CORPORATION

                                           By: /s/ Cregg Baumbaugh
                                              ----------------------------------
                                              Name: Cregg Baumbaugh
                                              Title: Executive Vice President --
                                                     Finance, Strategy and
                                                     Development

                                       10
<PAGE>   11

                                                                       EXHIBIT A

<TABLE>
<CAPTION>
Stockholder Name and Address           Number of Existing Shares      Number and Description of Existing Rights
----------------------------           -------------------------      -----------------------------------------
<S>                                    <C>                            <C>
Telephone and Data Systems, Inc.              35,570,493                              None
30 North LaSalle, Suite 4000
Chicago, IL 60602
Attention: LeRoy T. Carlson, Jr.,
President
Facsimile: 312-630-9299
</TABLE>

The Shares listed above are subject to a Stockholders Agreement executed among
the Stockholder and Deutsche Telekom AG, dated as of July 23, 2000 and an
Investor Agreement between Stockholder and VoiceStream dated as of September 17,
1999.

<PAGE>   12

                                                                       EXHIBIT B

                              POWERTEL STOCKHOLDERS

<TABLE>
<S>                                                   <C>
ITC Holding Corporation, Inc.                         614 West Bay Street
ITC Service Company                                   Tampa, FL 33606-2704
ITC Wireless, Inc.
3300 20th Avenue                                      ABOVE ADDRESS FOR THE FOLLOWING
Valley, AL 36854                                      STOCKHOLDERS:

                                                      Donald W. Burton

Sonera Holding, B.V.                                  The Burton Partnership, L.P., Donald W. Burton, General
c/o Sonera Corporation                                Partner
P.O. Box 106
FIN-00051-SONERA                                      The Burton Partnership (QP), L.P., Donald W. Burton,
Teollisuuskatu 15, Helsinki                           General Partner
Attn: Kaj-Erik Relander,
Deputy Chief Executive Officer
Facsimile: 011 358 2040 3770

Sonera Corporation                                    South Atlantic Venture Fund II, L.P., South Atlantic
P.O. Box 106                                          Venture Partners II, L.P., general partner, of which
FIN-00051-SONERA                                      Mr. Burton is managing general partner
Teollisuuskatu 15, Helsinki
Attn: Kaj-Erik Relander,                              South Atlantic Venture Fund III, L.P.; South Atlantic
Deputy Chief Executive Officer                        Partners III, L.P., sole general partner, of which Mr.
Facsimile: 011 358 2040 3770                          Burton is chairman

                                                      South Atlantic Private Equity Fund IV, L.P.; South
SCANA Communications Holdings, Inc.                   Atlantic Private Equity Partners IV, sole general
Delaware Avenue, Suite 510                            partner, of which Mr. Burton is chairman
Wilmington, DE 19801-1622

American Water Works Company                          South Atlantic Private Equity Fund IV (QP)
PO Box 1770                                           L.P.; South Atlantic Private Equity Partners
Voorhees, NJ 08043                                    IV, Inc., sole general partner, of which Mr.
                                                      Burton is chairman
</TABLE><PAGE>   1
                                                                    EXHIBIT 10.5

                                                             HUTCHISON AGREEMENT
                                                                  EXECUTION COPY

                       VOICESTREAM STOCKHOLDERS AGREEMENT

                  This VoiceStream Stockholders Agreement (this "Agreement")
dated as of August 26, 2000 among Powertel, Inc., a Delaware corporation
("Powertel"), each of the stockholders of VoiceStream listed on the signature
page hereto (each, a "Stockholder"), and VoiceStream Wireless Corporation, a
Delaware corporation ("VoiceStream") solely for purposes of Section 6.

                  WHEREAS, simultaneously with the execution of this Agreement,
VoiceStream and Powertel are entering into an Agreement and Plan of Merger (the
"Powertel Merger Agreement"), dated as of the date hereof, providing, among
other things, for the merger of a subsidiary of VoiceStream with and into
Powertel (the "Merger");

                  WHEREAS, Powertel has agreed to enter into the Powertel Merger
Agreement only if the VoiceStream Principal Stockholders enter into a
VoiceStream Voting Agreement, including this Agreement;

                  WHEREAS, in the Powertel Merger Agreement VoiceStream has
agreed, subject to the conditions set forth therein, to acquire all of the
shares of Powertel Common Stock (as defined below);

                  NOW THEREFORE, in consideration of the foregoing and the
mutual premises, representations, warranties, covenants and agreements contained
herein and in the Merger Agreement, the parties hereto, intending to be legally
bound hereby, agree as follows:

                  1.       Certain Definitions.

                  This Agreement is one of the VoiceStream Voting Agreements
referenced in the recitals to the Powertel Merger Agreement. For the purposes of
this Agreement, all capitalized terms used but not otherwise defined herein
shall have the respective meanings given to such terms in the Powertel Merger
Agreement.

                  For the purposes of this Agreement, the words "beneficially
owned" or "beneficial ownership" shall include, with respect to any securities,
the beneficial ownership by a Stockholder and by any direct or indirect
Subsidiary of a Stockholder.

                  "Transfer" means, with respect to any security, the sale,
transfer, pledge, hypothecation, encumbrance, assignment or other disposition of
such security or the record or beneficial ownership thereof, the offer to make
such a sale, transfer or other disposition, and each agreement, arrangement or
understanding, whether or not in writing, to effect any of the foregoing.

                  2.       Representations; Warranties and Covenants of Each
Stockholder. Each Stockholder hereby represents and warrants, severally and not
jointly, to Powertel, solely with respect to itself, as follows:

<PAGE>   2

                  (a)      Title. As of the date hereof, such Stockholder is the
sole record or beneficial owner of the number of shares of VoiceStream Common
Stock or VoiceStream preferred stock, as the case may be, set forth opposite
such Stockholder's name on Exhibit A attached hereto (with respect to each
Stockholder, such Stockholder's "Existing Shares" and, together with record or
beneficial ownership of any shares of VoiceStream Common Stock or other voting
capital stock of VoiceStream acquired after the date hereof, whether upon the
exercise of warrants or options, conversion of VoiceStream preferred stock or
any convertible securities or otherwise, such Stockholder's "Shares"), and/or
the number of warrants, options or other rights to acquire or receive such
VoiceStream Common Stock or VoiceStream preferred stock, as the case may be, set
forth opposite such Stockholder's name on Exhibit A attached hereto (with
respect to each Stockholder, such Stockholder's "Existing Rights" and, together
with record or beneficial ownership of any warrants, options or other rights to
acquire or receive such shares of VoiceStream Common Stock or other voting
capital stock of VoiceStream acquired after the date hereof, such Stockholder's
"Rights"). Such Stockholder is the lawful owner of the Existing Shares and
Existing Rights, free and clear of all liens, claims, charges, security
interests or other encumbrances, except as disclosed on Exhibit A. As of the
date hereof, the Existing Shares constitute all of the capital stock of
VoiceStream owned of record or beneficially by such Stockholder (excluding the
Existing Rights) and such Stockholder does not own of record or beneficially, or
have the right to acquire (whether currently, upon lapse of time, following the
satisfaction of any conditions, upon the occurrence of any event or any
combination of the foregoing) any shares of VoiceStream Common Stock or
VoiceStream preferred stock or any other securities convertible into or
exchangeable or exercisable for shares of VoiceStream Common Stock, except
pursuant to the Existing Rights.

                  (b)      Right to Vote. Except as disclosed on Exhibit A, such
Stockholder has, and (subject to the provisions of Section 3(a)) will have at
the VoiceStream Stockholders' Meeting, with respect to all of such Stockholder's
Shares listed on Exhibit A and acquired subsequent to the date hereof and prior
to the record date for the VoiceStream Stockholders' Meeting, sole voting power,
sole power of disposition or sole power to issue instructions with respect to
the matters set forth in Section 4 hereof and to fulfill its obligations under
such Section and shall not take any action or grant any person any proxy
(revocable or irrevocable) or power-of-attorney with respect to any Shares or
Rights inconsistent with his or its obligations as provided by Section 4 and
Section 5 hereof. Each Stockholder hereby revokes any and all proxies with
respect to such Stockholder's Existing Shares to the extent they are
inconsistent with the Stockholders' obligations under this Agreement.

                  (c)      Authority. Such Stockholder has full legal power,
authority, legal capacity and right to execute and deliver, and to perform its
or his obligations under, this Agreement. No proceedings or actions on the part
of such Stockholder other than those already taken are necessary to authorize
the execution, delivery or performance of this Agreement or the consummation of
the transactions contemplated hereby. This Agreement has been duly and validly
executed and delivered by such Stockholder and constitutes a valid and binding
agreement of such Stockholder enforceable against such Stockholder in accordance
with its terms, subject to (i) bankruptcy, insolvency, moratorium and other
similar laws now or hereafter in effect relating to or affecting creditors
rights generally and (ii) general principles of equity (regardless of whether
considered in a proceeding at law or in equity).

                                       2
<PAGE>   3

                  (d)      Conflicting Instruments. Neither the execution and
delivery of this Agreement nor the performance by such Stockholder of its
agreements and obligations hereunder will result in any breach or violation of,
or be in conflict with or constitute a default under, any term of any agreement,
judgment, injunction, order, decree, federal law or regulation to which such
Stockholder is a party or by which such Stockholder (or any of its assets) is
bound.

                  (e)      Powertel's Reliance. Such Stockholder understands and
acknowledges that Powertel is entering into the Powertel Merger Agreement in
reliance upon such Stockholder's execution, delivery and performance of this
Agreement.

                  3.       Restriction on Transfer; Other Restrictions.

                  (a)      From the date hereof until the later of January 1,
2001 and the date of the VoiceStream Stockholders' Meeting, each Stockholder
agrees not to Transfer any Shares or Rights owned of record or beneficially by
such Stockholder, except as otherwise permitted by this Section 3 or pursuant to
the Powertel Merger Agreement or the DT Merger Agreement, Transfers to any
Affiliate of the Stockholder who agrees in writing to be bound by the terms of
this Agreement or Transfers which occur by operation of law if the transferee
remains, or agrees in writing to remain, bound by the terms of this Agreement,
other than, in each case, with Powertel's prior written consent, provided,
however, that this Section 3(a) shall cease to be of any force or effect
immediately upon termination of the Powertel Merger Agreement.

                  (b)      Each Stockholder agrees that if at any time during
the period beginning on the later of January 1, 2001 and the date of the
VoiceStream Stockholders' Meeting and continuing until the first to occur of (1)
the Effective Time and (2) the termination of the Powertel Merger Agreement, the
Stockholders propose to Transfer, or exercise or propose to exercise
registration rights with respect to, more than 25% of the Stockholders' Shares
(individually or in the aggregate with other Transfers made during such period),
such Stockholder will notify the Powertel stockholders listed on Exhibit B
attached hereto ("the "Powertel Stockholders") in writing at the addresses set
forth on Exhibit B at least three Business Days in advance of such proposed
Transfer or exercise of rights, whichever is first to occur, and shall waive any
right of such Stockholder to preclude or delay the filing of a registration
statement or a Transfer by the Powertel Stockholders with respect to Powertel
Stock up to the amounts permitted under Section 3.3 of such Powertel
Stockholders' Powertel Stockholders Agreements with VoiceStream (as such amounts
may be increased by the provisions of such Section 3.3).

                  (c)      Each Stockholder agrees that if at any time during
the period beginning on the Effective Time through and including the six (6)
month anniversary of the Effective Time, the Stockholders propose to Transfer,
or exercise or propose to exercise registration rights with respect to more than
such number of Shares that the Stockholders are permitted to Transfer under Rule
144 promulgated under the Securities Act, including the volume restriction
contained therein (individually or in the aggregate with other Transfers made
during such period), such Stockholder will notify the Powertel Stockholders in
writing at least three Business Days in advance of such proposed Transfer or
exercise of rights, whichever is first to occur, and, at the Stockholders'
option, either (i) allow each Powertel Stockholder to include a proportionate
percentage (i.e., a percentage equivalent to the ratio of the total number of
Shares offered for sale

                                       3
<PAGE>   4

by the Stockholders to the total number of Shares beneficially owned by the
Stockholders) of the total number of shares of VoiceStream Common Stock
beneficially owned by such Powertel Stockholder in any registration statement
requested to be filed by the Stockholders or (ii) shall waive any right that
such Stockholder may have to preclude or delay the filing of a registration
statement by any of the Powertel Stockholders covering a number of shares up to
that permitted under Section 3.4 of such Powertel Stockholders' Powertel
Stockholders Agreements with VoiceStream (as such number may be increased by the
provisions of such Section 3.4).

                  4.       Agreement to Vote. Each Stockholder hereby
irrevocably and unconditionally agrees to vote or to cause to be voted or
provide a consent with respect to, all Shares that he, she or it owns of record
or beneficially as of the record date for the VoiceStream Stockholders' Meeting
at the VoiceStream Stockholders' Meeting and at any other annual or special
meeting of stockholders of VoiceStream or action by written consent where such
matters arise in favor of the Powertel Merger Agreement and, if required, the
other transactions referenced in the Powertel Merger Agreement, and against the
liquidation or winding up of VoiceStream.

                  5.       Delivery of Proxy. In furtherance of the agreements
contained in Section 4 hereof, each Stockholder hereby agrees (a) to complete
and send the proxy card received by such Stockholder with the Joint Proxy
Statement, so that such proxy card is received by VoiceStream, as prescribed by
the Joint Proxy Statement, not later than the fifth Business Day preceding the
day of the VoiceStream Stockholders Meeting, (b) to vote, by completing such
proxy card but not otherwise, all the Shares he, she or it owns of record or
beneficially as of the record date for the VoiceStream Stockholder' Meeting (i)
in favor of the Powertel Merger Agreement and, if required, the other
transactions referenced in the Powertel Merger Agreement and (ii) if the
opportunity to do so is presented to such Stockholder on the proxy card, against
the liquidation or winding up of VoiceStream and (c) not to revoke any such
proxy.

                  6.       Amendment of Existing Voting Agreements. The
Stockholders and certain other stockholders of VoiceStream are parties to a
Voting Agreement dated February 25, 2000 (as amended May 4, 2000), and a certain
First Amended and Restated Voting Agreement dated July 23, 2000 which will take
effect in accordance with its terms (collectively the "Existing Voting
Agreements") pursuant to which they have agreed to vote all shares of
VoiceStream Common Stock and VoiceStream preferred stock beneficially owned by
each of them at the time of such vote in the election of directors in accordance
with the procedures and provisions set forth in such agreements. On or before
the Effective Time, provided that the Stockholders are still subject to the
Existing Voting Agreements, VoiceStream and the Stockholders agree to execute
and deliver, and VoiceStream agrees that it will make commercially reasonable
efforts to cause the other parties to the Existing Voting Agreements to execute
and deliver, an amendment to the Existing Voting Agreements(the "Amended Voting
Agreement") on terms mutually satisfactory to VoiceStream, the Stockholders, the
Powertel Principal Stockholders (who will become parties to the Amended Voting
Agreement), and the other parties who are presently parties to the Existing
Voting Agreements, providing for: (i) the nomination of one representative of
the Powertel stockholders to the VoiceStream Board of Directors who shall be
initially designated by the Powertel Board of Directors and who shall also be
reasonably satisfactory to VoiceStream; (ii) the creation of a vacancy on the
VoiceStream Board of Directors (and the approval of any Bylaw amendments or
other actions required to do so); (iii)

                                       4
<PAGE>   5

the appointment of such nominee (and any successor nominee) to a newly created
vacancy on the VoiceStream Board of Directors; and (iv) an agreement to vote all
shares of VoiceStream Common Stock and other voting securities of VoiceStream
(and all securities received in exchange, replacement or substitution therefore,
or as a dividend or result of a stock split with respect thereto) owned of
record or beneficially by the Stockholders at the time of such vote for such
nominee (and any successor nominee) at the first two annual meetings after the
Effective Time. If VoiceStream and the Stockholders are unable to cause the
execution of an Amended Voting Agreement, they shall execute a separate voting
agreement with the Powertel Principal Stockholders and such other VoiceStream
stockholders who agree to enter into such separate voting agreement on terms and
conditions substantially similar to the Existing Voting Agreements making the
same additional provisions as set forth in the preceding sentence. Prior to the
Effective Time, the Powertel Board of Directors may make such provisions as it
deems appropriate for successor nominees each of which shall be reasonably
satisfactory to VoiceStream. After the Effective Time, any nominee or successor
nominee shall be selected by mutual agreement of ITC Holding Company, Inc., a
Delaware corporation ("ITCORP") and SCANA Communications Holdings, Inc., a
Delaware corporation ("SCORP") or, if no such agreement can be reached, by
whichever of ITCORP and SCORP beneficially owns the larger number of shares of
VoiceStream Common Stock and VoiceStream preferred stock (on an as-if-converted
basis).

                  7.       Additional Shares and Additional Rights. If, after
the date hereof, a Stockholder acquires record or beneficial ownership of any
additional shares of capital stock of VoiceStream (any such shares, "Additional
Shares"), including, without limitation, upon exercise of any option, warrant or
right to acquire shares of capital stock of VoiceStream, through the conversion
of the VoiceStream preferred stock or through any stock dividend or stock split
(any such options, warrants or rights, "Additional Rights"), the provisions of
this Agreement applicable to the Shares shall be applicable to such Additional
Shares and Additional Rights from and after the date of acquisition thereof. The
provisions of the immediately preceding sentence shall be effective with respect
to Additional Shares without action by any Person immediately upon the
acquisition by any Stockholder of record or beneficial ownership of such
Additional Shares or Additional Rights.

                  8.       Miscellaneous.

                  (a)      Entire Agreement. This Agreement constitutes the
entire agreement among the parties with respect to the subject matter hereof.

                  (b)      Costs and Expenses. All costs and expenses incurred
in connection with this Agreement and the transactions contemplated hereby shall
be paid by the party incurring such expenses.

                  (c)      Invalid Provisions. If any provision of this
Agreement shall be invalid or unenforceable under applicable law, such provision
shall be ineffective to the extent of such invalidity or unenforceability only,
without it affecting the remaining provisions of this Agreement.

                                       5
<PAGE>   6

                  (d)      Execution in Counterparts. This Agreement may be
executed in counterparts transmitted and delivered by facsimile each of which
shall be an original with the same effect as if the signatures hereto and
thereto were upon the same instrument.

                  (e)      Specific Performance. Each Stockholder agrees with
Powertel as to himself or itself that if for any reason such Stockholder fails
to perform any of his or its agreements or obligations under this Agreement,
irreparable harm or injury to Powertel would be caused as to which money damages
would not be an adequate remedy. Accordingly, each Stockholder agrees that, in
seeking to enforce this Agreement against such Stockholder, Powertel shall be
entitled, in addition to any other remedy available at law, equity or otherwise,
to specific performance and injunctive and other equitable relief. The
provisions of this Section 8(e) are without prejudice to any other rights or
remedies, whether at law or in equity, that Powertel may have against such
Stockholder for any failure to perform any of its agreements or obligations
under this Agreement.

                  (f)      Amendments; Termination.

                           (i)      This Agreement, including this Section 8(f),
         may not be modified, amended, altered or supplemented, except upon the
         execution and delivery of a written agreement executed by the parties
         hereto.

                           (ii)     The provisions of this Agreement (other than
         Sections 3, 4 and 6) shall terminate upon the earliest to occur of (A)
         the consummation of the Merger, (B) the date that is two (2) years
         after the date hereof, and (C) the termination of the Merger Agreement.
         The provisions of Sections 3(a), 3(b) and 4 of this Agreement shall
         terminate when the applicable time periods set forth in Section 3
         lapse, and the provisions of Section 3(c) shall terminate on the
         earlier of the six (6) month anniversary of the Effective Time or upon
         the termination of the Powertel Merger Agreement. The provisions of
         Section 6 shall terminate upon earlier of the execution and delivery of
         a new or amended voting agreement or the termination of the Powertel
         Merger Agreement.

                  (g)      Governing Law; Submission and Jurisdiction.

                           (i)      This Agreement shall be governed by and
         construed in accordance with the laws of the State of Delaware without
         giving effect to the principles of conflicts of laws thereof.

                           (ii)     Each of the parties hereto irrevocably
         agrees that any legal action or proceeding with respect to this
         Agreement or for recognition and enforcement of any judgment in respect
         hereof brought by the other party hereto or its successors or assigns
         shall be brought and determined only in the United States District
         Court for the State of Delaware or, in the event (but only in the
         event) that such court does not have subject matter jurisdiction over
         such action or proceeding, in the courts of the State of Delaware. Each
         of the parties hereto hereby irrevocable submits with regard to any
         such action or proceeding for itself and in respect to its property,
         generally and unconditionally, to the personal jurisdiction of the
         aforesaid courts. Each of the parties hereto hereby irrevocably waives,
         and agrees not to assert, by way of motion, as a defense,

                                       6
<PAGE>   7

         counterclaim or otherwise, in any action or proceeding with respect to
         this Agreement, (A) any claim that it is not personally subject to the
         jurisdiction of the above-named courts for any reason other than the
         failure to serve in accordance with this Section 8(g)(ii) or that it or
         its property is exempt or immune from jurisdiction of any such court or
         from any legal process commenced in such courts (whether through
         service of notice, attachment prior to judgment, attachment in aid of
         execution of judgment, execution of judgment or otherwise), and (B) to
         the fullest extent permitted by the applicable law, that (x) the suit,
         action or proceeding in such court is brought in an inconvenient forum,
         (y) the venue of such suit, action or proceeding is improper and (z)
         this Agreement, or the subject matter hereof, may not be enforced in or
         by such courts. Without limiting the foregoing, each party agrees that
         service of process on such party as provided in Section 8(i) shall be
         deemed effective service of process on such party.

                  (h)      Successors and Assigns. The provisions of this
Agreement shall be binding upon and inure to the benefit of the parties hereto
and their respective legal successors (including, in the case of such
Stockholder or any other individual, any executors, administrators, estates,
legal representatives and heirs of such Stockholder or such individual) and
permitted assigns; provided that, except as otherwise provided in this
Agreement, no party may assign, delegate or otherwise transfer any of its rights
or obligations under this Agreement.

                  (i)      Notices. All notices and other communications given
or made pursuant hereto shall be in writing and shall be deemed to have been
duly given or made as of the date of receipt and shall be delivered personally
or sent by overnight courier or sent by telecopy, to the Parties at the
following addresses or telecopy numbers (or at such other address or telecopy
number for a party as shall be specified by like notice):

                           (i)      if to a Stockholder, at such Stockholder's
         address appearing on Exhibit A hereto or at any other address that such
         Stockholder may have provided in writing to Powertel and the other
         Stockholders,

                           with a copy to:

                                    Preston Gates & Ellis LLP
                                    701 Fifth Avenue, Suite 5000
                                    Seattle, WA 98104
                                    Attn: Richard B. Dodd, Esq.
                                    Telecopy No: 206-623-7022

                           And a copy to:

                                    Friedman, Kaplan & Seiler LLP
                                    875 Third Avenue
                                    New York, New York 10022
                                    Attention: Barry A. Adelman
                                    Facsimile: 212-355-6401

                                       7
<PAGE>   8

                           (ii)     if to Powertel:

                                    Powertel, Inc.
                                    1239 O.G. Skinner Drive
                                    West Point, GA 31833
                                    Attention: Chairman of the Board
                                    Facsimile: 706-645-9563

                           with a copy to:

                                    Morris Manning & Martin, L.L.P.
                                    1600 Atlanta Financial Center
                                    3343 Peachtree Road, NE
                                    Atlanta, Georgia 30326
                                    Attention: James Walker IV
                                    Facsimile: 404-365-9532

                  (j)      Third Party Beneficiaries. This Agreement is entered
into solely for the benefit of the parties hereto and no person other than such
parties, and their respective successors and permitted assigns to the extent
expressly provided herein, may exercise any right or enforce any obligation
hereunder; provided, however, that the Powertel Stockholders shall be deemed to
be third party beneficiaries of this Agreement solely with respect to the
notification provisions contained in Sections 3(b) and 3(c) hereof.

                                       8
<PAGE>   9

                     STOCKHOLDERS SIGNATURE PAGE - HUTCHISON

                  IN WITNESS WHEREOF, the parties hereto have executed this
VoiceStream Stockholders Agreement as of this 26th day of August, 2000.

                                           VOICESTREAM WIRELESS
                                           CORPORATION

                                           By: /s/ CREGG BAUMBAUGH
                                              ----------------------------------
                                              Name:  Cregg Baumbaugh
                                              Title: Executive Vice President --
                                                     Finance, Strategy &
                                                     Development

                                           POWERTEL, INC.

                                           By: /s/ ALLEN E. SMITH
                                              ----------------------------------
                                              Name:  Allen E. Smith
                                              Title: President and
                                                     Chief Executive Officer

                                           HUTCHISON TELECOMMUNICATIONS
                                              PCS (USA) LIMITED

                                           By: /s/ CANNING FOK
                                              ----------------------------------
                                              Name:  Canning Fok
                                              Title: Director

                                           HUTCHISON TELECOMMUNICATIONS
                                              HOLDINGS (USA) LIMITED.

                                           By: /s/ SUSAN CHOW
                                              ----------------------------------
                                              Name:  Susan Chow
                                              Title: Director

                                       9
<PAGE>   10

                                                                       EXHIBIT A

<TABLE>
<CAPTION>
Stockholder Name and Address                     Number of Existing Shares        Number and  Description
----------------------------                     -------------------------        -----------------------
                                                                                  of Existing Rights
                                                                                  ------------------
<S>                                          <C>                                  <C>
Hutchison Telecommunications PCS (USA)                   52,010,364
Limited                                         (Which includes 26,227,586
c/o Offshore Incorporations Limited           shares of Common stock issuable
P.O. Box 957                                 upon conversion of the Company's
Offshore Incorporations Centre                    2.5% Junior Convertible
Road Town, Tortola                                    Preferred Stock)
British Virgin Islands
Telephone No.: 809-494-2233
Facsimile No.: 809-494-4885

and:

c/o Hutchison Telecommunications Limited
22nd Floor, Hutchison House
10 Harcourt Road
Hong Kong
Attention: Ms. Edith Shih
Fax: 852-2128-1778

Hutchison Telecommunications Holdings                    3,888,888
(USA) Limited

c/o Offshore Incorporations Limited
P.O. Box 957
Offshore Incorporations Centre
Road Town, Tortola
British Virgin Islands
Telephone No.: 809-494-2233
Facsimile No.: 809-494-4885

and:

c/o Hutchison Telecommunications Limited
22nd Floor, Hutchison House
10 Harcourt Road
Hong Kong
Attention: Ms. Edith Shih
Fax: 852-2128-1778
                                                       55,899,252
                                                       ----------
</TABLE>

The Shares listed above are subject to a Stockholders Agreement executed among
the Stockholders and Deutsche Telekom AG, dated as of July 23, 2000.

<PAGE>   11

                                                                       EXHIBIT B

                              POWERTEL STOCKHOLDERS

<TABLE>
<S>                                                  <C>
ITC Holding Corporation, Inc.                        614 West Bay Street
ITC Service Company                                  Tampa, FL 33606-2704
ITC Wireless, Inc.
3300 20th Avenue                                     ABOVE ADDRESS FOR THE FOLLOWING
Valley, AL 36854                                     STOCKHOLDERS:

                                                     Donald W. Burton

Sonera Holding, B.V.                                 The Burton Partnership,  L.P., Donald W. Burton,
c/o Sonera Corporation                               General Partner
P.O. Box 106
FIN-00051-SONERA                                     The Burton  Partnership  (QP),  L.P.,  Donald W.
Teollisuuskatu 15, Helsinki                          Burton, General Partner
Attn: Kaj-Erik Relander,
Deputy Chief Executive Officer
Facsimile: 011 358 2040 3770

Sonera Corporation                                   South Atlantic Venture Fund II, L.P., South
P.O. Box 106                                         Atlantic Venture Partners II, L.P.,  general
FIN-00051-SONERA                                     partner, of which Mr. Burton is managing
Teollisuuskatu 15, Helsinki                          general partner
Attn: Kaj-Erik Relander,
Deputy Chief Executive Officer                       South Atlantic Venture Fund III, L.P.; South
Facsimile: 011 358 2040 3770                         Atlantic Partners III, L.P., sole
                                                     general partner, of which Mr. Burton is
                                                     chairman

                                                     South Atlantic Private Equity Fund IV, L.P.;
SCANA Communications Holdings, Inc.                  South Atlantic Private Equity  Partners IV, sole
Delaware Avenue, Suite 510                           general partner, of which Mr. Burton is
Wilmington, DE 19801-1622                            chairman

American Water Works Company                         South Atlantic Private Equity Fund IV (QP)
PO Box 1770                                          L.P.; South Atlantic Private Equity Partners
Voorhees, NJ 08043                                   IV, Inc., sole general partner, of which Mr.
                                                     Burton is chairman
</TABLE>

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00014-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00014-of-00352.parquet"}]]