<PAGE>

                                                                     EXHIBIT 2.2


                          TENDER AND VOTING AGREEMENT

     THIS TENDER AND VOTING AGREEMENT, dated as of April 2, 2001 (this
"Agreement"), is entered into by and between 3D Systems Corporation, a Delaware
corporation ("Parent"), and Tiger Deals, Inc., a Delaware corporation and an
indirect wholly-owned subsidiary of Parent ("Buyer"), on the one hand, and DTM
Acquisition Company, L.P. ("Shareholder"), on the other hand. Capitalized terms
used herein but not otherwise defined shall have the meanings set forth in the
Merger Agreement (as defined below).

                                   RECITALS:

     WHEREAS, concurrently herewith, Parent, Buyer and Dragon, a Texas
corporation (the "Company"), are entering into an Agreement and Plan of Merger,
of even date herewith (the "Merger Agreement"), pursuant to which Buyer will
make a tender offer (the "Offer") for all outstanding shares of common stock,
$0.0002 par value, of the Company ("Company Common Stock") and, after Buyer has
accepted tendered shares for payment (the date on which such acceptance occurs,
the "Acceptance Date"), the Company and Buyer will be merged together, with the
Company as the surviving corporation and an indirect wholly-owned subsidiary of
Parent (the "Merger");

     WHEREAS, Shareholder Beneficially Owns (as defined herein) 3,509,357 shares
of Company Common Stock (the "Shares"); and

     WHEREAS, as an inducement and a condition to entering into the Merger
Agreement, Parent and Buyer have required that Shareholder agree, and
Shareholder has agreed, to enter into this Agreement.

     NOW, THEREFORE, in consideration of the foregoing and the mutual premises,
representations, warranties, covenants and agreements contained herein, the
parties hereto hereby agree as follows:

     Section 1. Tender of Shares.
                ----------------

     (a)  Shareholder hereby agrees with Parent and Buyer that Shareholder will,
promptly after the date of commencement of the Offer (but in all events not
later than ten (10) Business Days thereafter, or if Shareholder has not received
the Offer Documents by such time, within two (2) Business Days following receipt
of such documents but in any event prior to the Acceptance Date), tender to
Buyer or its agent, in accordance with the Offer, all Shares Beneficially Owned
by Shareholder on such date (the "Tendered Shares"). Shareholder further agrees
to tender to Buyer or its agent promptly after Shareholder's acquisition thereof
(but in all events not later than ten (10) Business Days after such acquisition
and in any event prior to the Acceptance Date) all other shares of Company
Common Stock acquired and Beneficially Owned by Shareholder at any time prior to
the Acceptance Date or the date on which the Offer is terminated or expires
without Buyer's having accepted shares for payment; all such subsequently
tendered Shares shall

                                       1
<PAGE>

constitute "Tendered Shares" for all purposes of this Agreement. Shareholder
agrees not to withdraw any of the Tendered Shares unless the Offer is terminated
or has expired without Buyer having accepted the Tendered Shares for payment.
Shareholder acknowledges and agrees that Buyer's obligation to accept for
payment and pay for the Tendered Shares is subject to all the terms and
conditions of the Offer. Shareholder hereby permits Parent and Buyer to publish
and disclose in the Offer Documents and, if approval of the Company Shareholders
is required under applicable Law, any Company Proxy Statement (including all
documents and schedules filed with the SEC), if any, its identity and ownership
of the Shares and the nature of its commitments, arrangements and understandings
under this Agreement.

     (b)      Shareholder will receive the same Offer Price received by the
Company Shareholders in the Offer with respect to the Tendered Shares.

     Section 2. Voting Agreement.
                ----------------

     (a)  Shareholder hereby agrees with Parent and Buyer that, at a meeting of
the Company Stockholders, if any, however called, or in connection with any
written consent of the Company Shareholders in lieu of a meeting, Shareholder
shall vote the Shares Beneficially Owned by Shareholder, whether heretofore
owned or hereafter acquired, (i) in favor of approval of the Merger Agreement
and any actions required in furtherance of the Transactions, including without
limitation voting such Shares in favor of the election to the Company Board and
the Board of Directors of each Acquired Subsidiary of each person designated by
Parent for nomination thereto pursuant to Section 2.3(a) of the Merger Agreement
at any meeting of the Company Shareholders called for the election of directors;
(ii) against any action or agreement that would result in a breach in any
respect of any covenant, representation or warranty or any other obligation or
agreement of the Company under the Merger Agreement; and (iii) except as
otherwise agreed to in writing in advance by Parent, against: (A) any
Acquisition Proposal, (B) any change in a majority of the individuals who, as of
the date hereof, constitute the Company Board (other than as contemplated by
Section 2.3(a) of the Merger Agreement), (C) any extraordinary corporate
transaction, such as a merger, consolidation or other business combination
involving the Company or any of the Acquired Subsidiaries and any other Person,
(D) a sale, lease, transfer or disposition of any assets of the Company's or any
Acquired Subsidiary's business outside the Ordinary Course of Business, or any
assets which are material to its business whether or not in the Ordinary Course
of Business, or a reorganization, recapitalization, dissolution or liquidation
of the Company or any of the Acquired Subsidiaries, (E) any change in the
present capitalization of the Company or any amendment of the Company's
Organizational Documents, (F) any other material change in the Company's or any
Acquired Subsidiary's corporate structure or affecting its business, or (G) any
other action which is intended, or is likely, to impede, interfere with, delay,
postpone or have a material adverse effect on the Offer, the Merger or any of
the other Transactions.

     (b)  Shareholder shall not enter into any agreement or understanding with
any Person the effect of which would be inconsistent or violative of the
provisions and agreements contained herein.

                                       2
<PAGE>

     (c)  For purposes of this Agreement, "Beneficially Own" or "Beneficial
Ownership" with respect to any securities shall mean Shareholder's having such
ownership, control or power to direct the voting with respect to, or otherwise
enables Shareholder to legally act with respect to, such securities as
contemplated hereby, including pursuant to any agreement, arrangement or
understanding, whether or not in writing. Securities Beneficially Owned by
Shareholder shall (i) include securities Beneficially Owned by all other Persons
with whom Shareholder would constitute a "group" as within the meaning of
Section 13(d)(3) of the Exchange Act, and (ii) exclude, until their issuance,
any Shares issuable upon exercise of options held by Shareholder.

     Section 3. Shareholder Capacity.  Parent and Buyer acknowledge and
                --------------------
agree that Shareholder executes and delivers this Agreement solely in his
capacity as the record holder and beneficial owner of his Shares and no
provision of this Agreement shall limit or otherwise restrict Shareholder with
respect to any act or omission that Shareholder may undertake or authorize in
his capacity as an officer of the Company or a member of the Company Board,
including, without limitation, any vote that Shareholder may make as a director
of the Company with respect to any matter presented to the Company Board.

     Section 4. Grant of Irrevocable Proxy; Appointment of Proxy.
                ------------------------------------------------

     (a)  Shareholder hereby irrevocably grants to and appoints Parent as
Shareholder's proxy and attorney-in-fact (with full power of substitution), for
and in the name, place and stead of Shareholder, to vote the Shares to approve
and vote in favor of the Offer, the Merger Agreement and the other Transactions,
against any Acquisition Proposal and otherwise as contemplated by Section 2.

     (b)  Shareholder represents that any proxies heretofore given in respect of
the Shares are revocable, and that any such proxies are hereby revoked.

     (c)  Shareholder hereby affirms that the irrevocable proxy set forth in
this Section 4 is given in connection with the execution of the Merger Agreement
and affirms that the irrevocable proxy is coupled with an interest and may under
no circumstances be revoked until the termination of this Agreement pursuant to
Section 11.  Shareholder hereby ratifies and confirms all that such irrevocable
proxy may lawfully do or cause to be done by virtue hereof. THIS PROXY AND POWER
OF ATTORNEY IS IRREVOCABLE AND COUPLED WITH AN INTEREST.  Shareholder shall
execute and deliver to Parent any proxy cards that Shareholder receives to vote
in favor of the consummation of the Merger. Parent shall deliver to the
Secretary of the Company any such proxy cards received by it at any meeting
called to approve the consummation of the Merger.

     Section 5. Waiver Of Appraisal Rights.  Commencing on the date hereof
                --------------------------
and continuing until the termination of this Agreement, Shareholder hereby
irrevocably and unconditionally waives, and agrees to cause to be waived and to
prevent the exercise of, any rights of appraisal, any dissenters' rights and any
similar rights relating to the Merger or any of the Transactions that
Shareholder or any other Person may have by virtue of the ownership of any
Shares.

                                       3
<PAGE>

     Section 6. Spousal Consent.  If Shareholder is or may be subject to the
                ---------------
community property laws of any state or other jurisdiction, Shareholder will use
best efforts to cause his/her spouse to execute an acknowledgment and consent
consenting to and agreeing to the transactions contemplated by this Agreement.
Such consent will survive until the termination of this Agreement pursuant to
Section 11 hereof.

     Section 7. Other Covenants, Representations and Warranties.
                -----------------------------------------------
Shareholder hereby covenants, represents and warrants to Parent and Buyer as
follows:

     (a)  Ownership of Shares.  Shareholder is the Beneficial Owner of all the
Shares. On the date hereof, the Shares constitute all of the Shares Beneficially
Owned by Shareholder. Shareholder has voting power with respect to the matters
set forth in Section 2(a) hereof with respect to all of the Shares, with no
limitations, qualifications or restrictions on such rights.

     (b)  No Other Rights.  There are no outstanding options, warrants or rights
to purchase or acquire the Shares.

     (c)  Power; Binding Agreement.  Shareholder has the legal capacity, power
and authority to enter into and perform all of its obligations under this
Agreement. The execution, delivery and performance of this Agreement by
Shareholder will not violate any Contract or any Order to which Shareholder is a
party or is subject including, without limitation, any voting agreement or
voting trust. This Agreement has been duly and validly executed and delivered by
Shareholder and constitutes a valid and binding obligation on Shareholder
Enforceable in accordance with its terms.

     (d)  No Conflicts. Other than in connection with or in compliance with the
provisions of the Merger Agreement or the Exchange Act, no authorization,
consent or approval of, or filing with, any court or any public body or
authority is necessary for the consummation by Shareholder of the transactions
contemplated by this Agreement. The execution, delivery and performance of this
Agreement and the consummation of the transactions contemplated hereby will not
constitute a breach, violation or default (or any event which, with notice or
lapse of time or both, would constitute a default) under, or result in the
termination of, or accelerate the performance required by, or result in a right
of termination or acceleration under, or result in the creation of any
Encumbrance or claim upon any of the properties or assets of Shareholder under,
(i) the Organizational Documents of Shareholder, if any, or (ii) any note, bond,
mortgage, indenture, deed of trust, license, lease, agreement or other
instrument to which Shareholder is a party or by which its properties or assets
are bound.

     (e)  Restriction on Transfer, Proxies and Non-Interference.  Except as
expressly contemplated by this Agreement or the Merger Agreement, Shareholder
shall not, directly or indirectly: (i) offer for sale, sell, transfer, tender,
pledge, encumber, assign or otherwise dispose of, or enter into any contract,
option or other arrangement or understanding with respect to or consent to the
offer for sale, sale, transfer, tender, pledge, encumbrance, assignment or other
disposition of, any or all of the Shares or any interest therein; (ii) grant any
proxies or powers of attorney or deposit any Shares into a voting trust or enter
into a voting agreement with respect to

                                       4
<PAGE>

any Shares; or (iii) take any action that would make any representation or
warranty of Shareholder contained herein untrue or incorrect in any material
respect or have the effect of preventing or disabling Shareholder from
performing any of Shareholder's obligations under this Agreement.
Notwithstanding anything to the contrary provided in this Agreement, Shareholder
shall have the right to transfer Shares to (i) any Family Member (as defined
below), (ii) the trustee or trustees of trust for the benefit of Shareholder
and/or one or more Family Members and/or charitable organizations, (iii) a
partnership of which Shareholder and/or Family Members owns a majority of the
partnership interests, (iv) a limited liability company of which Shareholder
and/or any Family Members owns a majority of the membership interests, (v) the
executor, administrator or personal representative of the estate of Shareholder,
(vi) any guardian, trustee or conservator appointed with respect to the assets
of Shareholder; (vii) any wholly owned subsidiary or Affiliate of Shareholder,
as applicable; or (viii) as a dividend or distribution to any partner,
shareholder or member, as applicable, of Shareholder; provided that in the case
of any such transfer, the transferee shall, as a condition to such transfer,
execute an agreement to be bound by the terms of this Agreement, or terms
substantially identical thereto. "Family Member" shall have the meaning ascribed
to "Related Parties" under Section 672(c) of the Internal Revenue Code of 1986,
as amended.

     (f)  Other Potential Acquirors.  Shareholder shall immediately cease any
currently ongoing discussions or negotiations with any other Persons with
respect to any Acquisition Proposal. Shareholder shall not, directly or
indirectly, encourage, solicit, participate in or initiate discussions or
negotiations with or provide any information to any Person or group (other than
Parent and/or any designees of Parent and Buyer) concerning any Acquisition
Proposal. Shareholder shall promptly (and in any event within one Business Day
after becoming aware thereof) (i) notify Parent in the event the Shareholder
receives any proposal or inquiry concerning an Acquisition Proposal, including
the terms and conditions thereof and the identity of the party submitting such
proposal, and any request for confidential information in connection with a
potential Acquisition Proposal, (ii) provide a copy of any written agreements,
proposals or other materials Shareholder receives from any such person or group
(or its representatives), and (iii) advise Parent from time to time of the
status, at any time upon Parent's request, and promptly following any
developments concerning the same.  The provisions of this Section 7(f) shall be
applicable to Shareholder solely in Shareholder's capacity as a shareholder of
the Company and nothing contained in this Section 7(f) shall preclude
Shareholder, in Shareholder's capacity as a director or officer of the Company,
from taking any action permitted under Section 6.4 of the Merger Agreement.

     (g)  Reliance by Parent and Buyer.  Shareholder understands and
acknowledges that Parent and Buyer are entering into the Merger Agreement in
reliance upon Shareholder's execution and delivery of this Agreement.

     (h)  No Finder's Fees. No broker, investment banker, financial advisor or
other Person is entitled to any broker's, finder's, financial advisor's or other
similar fee or commission in connection with the transactions contemplated by
this Agreement based upon arrangements made by or on behalf of Shareholder.

                                       5
<PAGE>

     Section 8.  Representations and Warranties of Parent and Buyer.  Parent
                 --------------------------------------------------
and Buyer hereby, jointly and severally, represent and warrant to Shareholder as
follows:

     (a)  Organization.  Each of Parent and Buyer is a corporation duly
organized, validly existing and in good standing under the laws of the State of
Delaware.

     (b)  Power; Binding Agreement.  Each of Parent and Buyer has the requisite
corporate power and authority to enter into and perform all of its obligations
under this Agreement.  The execution, delivery and performance by Parent and
Buyer of this Agreement, and the consummation by them of the transactions
contemplated hereby, have been duly and validly authorized by the respective
Boards of Directors of Parent and Buyer and no other corporate or other action
or proceedings on the part of Parent and Buyer are necessary to authorize the
transactions contemplated hereby.  This Agreement has been duly and validly
executed and delivered by Parent and Buyer and constitutes a valid and binding
obligation on Parent and Buyer Enforceable in accordance with its terms.

     (c)  No Conflicts.  Other than in connection with or in compliance with the
provisions of the Merger Agreement or the Exchange Act, no material
authorization, consent or approval of, or filing with, any court or any public
body or authority is necessary for the consummation by Parent and Buyer of the
transactions contemplated by this Agreement.  The execution, delivery and
performance of this Agreement and the consummation of the transactions
contemplated hereby will not constitute a breach, violation or default (or any
event which, with notice or lapse of time or both, would constitute a default)
under, or result in the termination of, or accelerate the performance required
by, or result in a right of termination or acceleration under, or result in the
creation of any Encumbrance or claim upon any of the properties or assets of
Parent or Buyer under (i) the organizational documents of Parent or Buyer or
(ii) any provision of any material note, bond, mortgage, indenture, deed of
trust, license, agreement or other instrument to which Parent or Buyer is a
party or by which their properties or assets are bound.

     Section 9.  Representations and Warranties of Parent and Buyer. Each of
                 --------------------------------------------------
Parent and Buyer hereby represent and warrant to Shareholder that the Offer, the
Offer Documents and the Transactions will comply in all material respects with
the provisions of applicable federal securities laws. Parent and Buyer further
represent that the Offer Documents, on the date filed with the SEC and on the
date first published, sent or given to the Shareholders, will not contain any
untrue statement of a material fact or omit to state any material fact required
to be stated therein or necessary in order to make the statements made therein,
in light of the circumstances under which they were made, not misleading, except
that no representation is made by Parent or Buyer with respect to information
supplied by an Acquired Entity for inclusion in the Offer Documents.

     Section 10. Stop Transfer.  Shareholder agrees with, and covenants to,
                 -------------
Parent and Buyer that Shareholder shall not request that the Company register
the transfer (book-entry or otherwise) of any certificate or uncertificated
interest representing any Shares, unless such transfer is made pursuant to this
Agreement. In the event of a stock dividend or distribution, or

                                       6
<PAGE>

any change in the Company Common Stock by reason of any stock dividend, split-
up, recapitalization, combination, exchange of shares or the like, the term
"Shares" shall be deemed to refer to and include the Shares as well as all such
stock dividends and distributions and any shares into which or for which any or
all of the Shares may be changed or exchanged.

     Section 11. Termination.  Shareholder's covenants and agreements contained
                 -----------
herein with respect to the Shares shall terminate upon the earliest to occur of:
(a) the termination of the Merger Agreement in accordance with its terms and (b)
the Acceptance Date. Upon the termination of this Agreement, this Agreement
shall forthwith become null and void, and there shall be no liability on the
part of any party hereto, except (i) that the provisions of this Section 11 and
the provisions of Section 12 shall survive the termination of this Agreement and
(ii) nothing herein shall relieve any party hereto from liability for any
intentional breach hereof committed prior to the termination of this Agreement.

     Section 12. Miscellaneous.
                 -------------

     (a)  Entire Agreement.  This Agreement constitutes the entire agreement
between the parties with respect to the subject matter hereof and supersedes all
other prior agreements and understandings, both written and oral, among the
parties with respect to the subject matter hereof.

     (b)  Certain Events.  Shareholder agrees that this Agreement and the
obligations hereunder shall attach to the Shares and shall be binding upon any
person to which legal or beneficial ownership of any Shares shall pass, whether
by operation of Law or otherwise. Notwithstanding any transfer of Shares, the
transferor shall remain liable for the performance of all obligations under this
Agreement of the transferor.

     (c)  Assignment.  This Agreement shall not be assigned by operation of Law
or otherwise without the prior written consent of the other parties; provided,
however, that Parent may, in its sole discretion, assign its rights and
obligations hereunder to any direct or indirect wholly-owned subsidiary of
Parent; provided further that such assignment shall not relieve Parent of its
obligations hereunder if such subsidiary shall fail to perform such obligations
in accordance with the terms of this Agreement.  Subject to the preceding
sentence, this Agreement shall be binding upon, inure to the benefit of and be
Enforceable by the parties and their respective successors and assigns.

     (d)  Amendments, Waivers, Etc.  This Agreement may not be amended, changed,
supplemented, waived or otherwise modified or terminated, except upon the
execution and delivery of a written agreement executed by the parties hereto.

     (e)  Notices. All notices, requests, demands, claims and other
communications hereunder will be in writing. Any Party may send any notice,
request, demand, claim, or other communication hereunder to the intended
recipient at the address set forth below using any other means (including
personal delivery, expedited courier, messenger service, telecopy, telex,
ordinary mail, or electronic mail), but no such notice, request, demand, claim,
or other

                                       7
<PAGE>

communication will be deemed to have been duly given unless and until it
actually is received by the intended recipient. Any Party may change the address
to which notices, requests, demands, claims, and other communications hereunder
are to be delivered by giving the other Parties notice in the manner herein set
forth below:

If to Parent and after Closing to the Acquired Entities:

            c/o 3D Systems Corporation
            26081 Avenue Hall
            Valencia, CA 91355
     Attn:  Chief Financial Officer

     Fax:   (661) 294-7966

     Copy to (which will not constitute notice):

     Akin, Gump, Strauss, Hauer & Feld, L.L.P.
     Attn:  Julie M.  Kaufer, Esq.
            2029 Century Park East, Suite 2600
            Los Angeles, CA 90067
     Fax:   (310) 229-1001

If to the Company and before Closing to the Acquired Entities:

            DTM Corporation
            1611 Headway Circle,
            Building 2
            Austin, Texas 78754
     Attn:  John S. Murchison, III

     Fax:   (512) 339-0634


     Copy to (which will not constitute notice):
     Brobeck, Phleger & Harrison, LLP
     Attn:  J. Matthew Lyons, P.C.
            4801 Plaza on the Lake
            Austin, Texas 78746

     Fax:   (512) 330-4001

     If to the Shareholder, to the address set forth under Shareholder's
signature on the signature page, and in the case of Proactive finance Group,
LLP:

                                       8
<PAGE>

     Copy to (which will not constitute notice):
     Locke Liddell & Sapp
     Attn:  Curtis Ashmos, Esq.
            100 Congress Avenue
            Suite 300
            Austin, TX 78701

     (f)  Severability. The provisions of this Agreement will be deemed
severable and the invalidity or unenforceability of any provision will not
affect the validity or enforceability of the other provisions hereof; provided
that if any provision of this Agreement, as applied to any party hereto or to
any circumstance, is adjudged by a Governmental Entity, arbitrator, or mediator
not to be enforceable in accordance with its terms, the parties agree that the
Governmental Entity, arbitrator, or mediator making such determination will have
the power to modify the provision in a manner consistent with its objectives
such that it is enforceable, and/or to delete specific words or phrases, and in
its reduced form, such provision will then be enforceable and will be enforced.

     (g)  Specific Performance. Each party hereto acknowledges and agrees that
the other parties would be damaged irreparably if any provision of this
Agreement is not performed in accordance with its specific terms or is otherwise
Breached.  Accordingly, each party hereto agrees that the other parties will be
entitled to an injunction or injunctions to prevent Breaches of the provisions
of this Agreement and to enforce specifically this Agreement and its terms and
provisions in any Action instituted in any court of the United States or any
state thereof having jurisdiction over the parties and the matter, subject to
Subsection (k) below, in addition to any other remedy to which they may be
entitled, at Law or in equity.

     (h)  Further Assurances.  From time to time, at a party's request and
without further consideration, the other party shall execute and deliver such
additional documents and take all such further lawful action as may be necessary
or desirable to consummate and make effective, in the most expeditious manner
practicable, the transactions contemplated by this Agreement.

     (i)  Remedies Cumulative.  All rights, powers and remedies provided under
this Agreement or otherwise available in respect hereof at Law or in equity
shall be cumulative and not alternative, and the exercise of any right, power or
remedy by any party hereto shall not preclude the simultaneous or later exercise
of any other such right, power or remedy by such party.

     (j)  No Waiver.  The failure of any party hereto to exercise any right,
power or remedy provided under this Agreement or otherwise available in respect
hereof at Law or in equity, or to insist upon compliance by any other party
hereto with its obligations hereunder, and any custom or practice of the parties
at variance with the terms hereof, shall not constitute a waiver by such party
of its right to exercise any such or other right, power or remedy or to demand
such compliance.

                                       9
<PAGE>

     (k)  Governing Law.  This Agreement and the performance of the obligations
of the parties will be governed by and construed in accordance with the Laws of
the State of Delaware, without giving effect to any choice of Law principles.

     (l)  WAIVER OF JURY TRIAL. THE PARTIES HERETO WAIVE ALL RIGHT TO TRIAL BY
JURY IN ANY ACTION OR PROCEEDING TO ENFORCE OR DEFEND ANY RIGHTS UNDER THIS
AGREEMENT AND ANY DOCUMENT EXECUTED IN CONNECTION HEREWITH.

     (m)  Counterparts.  This Agreement may be executed in counterparts, each of
which shall be deemed to be an original, but all of which, taken together, shall
constitute one and the same instrument.

     (n)  Descriptive Headings.  The descriptive headings contained in this
Agreement are inserted for convenience only and will not affect in any way the
meaning or interpretation of this Agreement.

                        [Signatures on following page]

                                       10
<PAGE>

     IN WITNESS WHEREOF, Parent, Buyer and Shareholder have executed and
delivered this Agreement as of the day and year first above written.

                                   3D SYSTEMS CORPORATION, a Delaware
                                   corporation


                                   By: /s/ Brian K. Service
                                       -----------------------------------------
                                   Name:   Brian K. Service
                                   Title:  President and Chief Executive Officer



                                   TIGER DEALS, INC., a Delaware corporation



                                   By: /s/ Brian K. Service
                                       -----------------------------------------
                                   Name:   Brian K. Service
                                   Title:  President and Chief Executive Officer



                                   SHAREHOLDER

                                   DTM ACQUISITION COMPANY, L.P.

                                   By:     Proactive  - DTM, L.P.,
                                           its General Partner

                                   By:     Proactive Finance Group, LLC,
                                           its General Partner


                                   By: /s/ Anthony Mariotti
                                       -----------------------------------------
                                   Name:   Anthony Mariotti
                                   Title:  Managing Member

                                   Address for Notices to Shareholder
                                   221 West 6th Street
                                   Suite 1520
                                   Austin, Texas 78701
                                   Facsimile:  (512) 320-8940

                                       11