<PAGE>   1

                                                                   EXHIBIT 10.56

                          STOCKHOLDERS PROXY AGREEMENT

     STOCKHOLDERS PROXY AGREEMENT (this "Agreement"), dated as of June 12, 2000,
among ELTRAX SYSTEMS, INC., a Minnesota corporation (the "Company"), and each
other person and entity listed on the signature pages hereof (each, a
"Stockholder").

                              W I T N E S S E T H:

     WHEREAS, as of the date hereof each Stockholder owns (either beneficially
or of record) the number of shares of common stock, par value $0.01 per share
("Cereus Common Stock"), of Cereus Technology Partners, Inc., a Delaware
corporation (the "Cereus"), set forth opposite such Stockholder's name on
Exhibit A hereto (all such shares of Cereus Common Stock owned by the
Stockholders and any shares of Cereus Common Stock hereafter acquired by the
Stockholders prior to the termination of this Agreement being referred to herein
as the "Shares");

     WHEREAS, Company and the Cereus, among others, propose to enter into an
Agreement and Plan of Merger and Reorganization, dated as of the date hereof (as
the same may be amended from time to time, the "Merger Agreement"; capitalized
terms herein not otherwise defined herein shall have the meanings ascribed
thereto in the Merger Agreement), which provides, upon the terms and subject to
the conditions thereof, for the merger of Cereus with and into a subsidiary of
Company (the "Merger"); and

     WHEREAS, as a condition to the willingness of Company to enter into the
Merger Agreement, Company has requested that each Stockholder agree, and, in
order to induce Company to enter into the Merger Agreement, each Stockholder has
agreed, to grant Company proxies to vote such Stockholder's Shares;

     NOW, THEREFORE, in consideration of the premises and of the mutual
agreements and covenants set forth herein and in the Merger Agreement, the
parties hereto agree as follows:

                                   ARTICLE I

                         TRANSFER AND VOTING OF SHARES

     SECTION 1.01  Transfer of Shares. During the term of this Agreement, and
except as otherwise provided herein, each Stockholder shall not (a) sell, pledge
or otherwise dispose of any of its Shares if such transaction would result in
the Stockholder no longer having the power to vote or cause to be voted the
Shares, (b) deposit its Shares into a voting trust or enter into a voting
agreement or arrangement with respect to such Shares or grant any proxy with
respect thereto or (c) enter into any contract, option or other arrangement or
undertaking with respect to the direct or indirect acquisition or sale,
assignment, transfer or other disposition of any of the Cereus Common Stock if
such transaction would result in the Stockholder no longer having the power to
vote or cause to be voted the Shares.

     Section 1.02  Voting of Shares; Further Assurances. (a) Each Stockholder,
by this Agreement, with respect to those Shares that it owns of record, does
hereby constitute and appoint Company, or any nominee of Company, with full
power of substitution, during and for the term of this Agreement, as its true
and lawful attorney and proxy, for and in its name, place and stead, to vote
each of such Shares as its proxy, at every annual, special or adjourned meeting
of the stockholders of the Cereus (including the right to sign its name (as
stockholder) to any consent, certificate or other document relating to the
Cereus that the law of the State of Delaware may permit or require) (i) in favor
of the adoption of the Merger Agreement and approval of the Merger and the other
transactions contemplated by the Merger Agreement, (ii) against any proposal for
any recapitalization, merger, sale of assets or other business combination
between the Cereus and any person or entity (other than the Merger) or any other
action or agreement that would result in a breach of any covenant,
representation or warranty or any other obligation
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or agreement of the Cereus under the Merger Agreement or which could result in
any of the conditions to the obligations of Cereus under the Merger Agreement
not being fulfilled, and (iii) in favor of any other matter relating to
consummation of the transactions contemplated by the Merger Agreement. Each
Stockholder further agrees to cause the Shares owned by it beneficially to be
voted in accordance with the foregoing. Each Stockholder acknowledges receipt
and review of a copy of the Merger Agreement.

     (b) Each Stockholder shall perform such further acts and execute such
further documents and instruments as may reasonably be required to vest in
Company the power to carry out the provisions of this Agreement.

     (c) Nothing contained in this Agreement shall be deemed to restrict a
Stockholder who is also a director of the Cereus from taking actions in his or
her capacity as a director as may be permitted under the Merger Agreement.

     SECTION 1.03  Term of Agreement. This Agreement shall be effective as of
the date hereof and shall expire on the earlier of (a) the Effective Time and
(b) the date of the termination of the Merger Agreement pursuant to its terms.

                                   ARTICLE II

                 REPRESENTATIONS AND WARRANTIES OF STOCKHOLDERS

     Each Stockholder, severally and not jointly, hereby represents and warrants
to Company as follows:

     SECTION 2.01  Due Organization, Etc. Such Stockholder (if it is a
corporation, partnership or other legal entity) is duly organized and validly
existing under the laws of the jurisdiction of its organization. Such
Stockholder has full power and authority (corporate or otherwise) to execute and
deliver this Agreement and to consummate the transactions contemplated hereby.
The execution and delivery of this Agreement and the consummation of the
transactions contemplated hereby have been duly authorized by all necessary
action (corporate or otherwise) on the part of such Stockholder. This Agreement
has been duly executed and delivered by or on behalf of such Stockholder and,
assuming its due authorization, execution and delivery by Company, constitutes a
legal, valid and binding obligation of such Stockholder, enforceable against
such Stockholder in accordance with its terms, subject to the effect of any
applicable bankruptcy, reorganization, insolvency, moratorium or similar laws
affecting creditors' rights generally and subject, as to enforceability, to the
effect of general principles of equity (regardless of whether such
enforceability is considered in a proceeding in equity or at law).

     Section 2.02  No Conflicts; Required Filings and Consents. (a) The
execution and delivery of this Agreement by such Stockholder do not, and the
performance of this Agreement by such Stockholder will not, (i) conflict with or
violate the Certificate of Incorporation or By-Laws or similar organizational
documents of such Stockholder (in the case of a Stockholder that is a
corporation, partnership or other legal entity), (ii) conflict with or violate
any law, rule, regulation, order, judgment or decree applicable to such
Stockholder or by which it or any of its properties is bound or affected, or
(iii) result in any breach of or constitute a default (or an event that with
notice or lapse of time or both would become a default) under, or give to others
any rights of termination, amendment, acceleration or cancellation of, or result
in the creation of a lien or encumbrance on any of the property or assets of
such Stockholder or (if such Stockholder is a corporation) any of its
subsidiaries pursuant to, any note, bond, mortgage, indenture, contract,
agreement, lease, license, permit, franchise or other instrument or obligation
to which such Stockholder is a party or by which such Stockholder or any of its
properties is bound or affected, except for any such breaches, defaults or other
occurrences that would not cause or create a material risk of non-performance or
delayed performance by such Stockholder of its obligations under this Agreement.

     (b) The execution and delivery of this Agreement by such Stockholder do
not, and the performance of this Agreement by such Stockholder will not, require
any consent, approval, authorization or permit of, or filing with or
notification to, any governmental or regulatory authority, domestic or foreign,
except (i) for applicable requirements, if any, of the Exchange Act, and the HSR
Act and (ii) where the failure

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to obtain such consents, approvals, authorizations or permits, or to make such
filings or notifications, would not prevent or delay the performance by such
Stockholder of its obligations under this Agreement.

     SECTION 2.03  Title to Shares. Other than to the extent described in
Exhibit A hereto, such Stockholder is the record or beneficial owner of its
Shares free and clear of any proxy or voting restriction other than pursuant to
this Agreement.

                                  ARTICLE III

                 REPRESENTATIONS AND WARRANTIES OF THE COMPANY

     The Company hereby represents and warrants to each Stockholder as follows:

     SECTION 3.01  Due Organization, Etc. The Company is a corporation duly
organized and validly existing under the laws of the State of Minnesota. The
Company has all necessary corporate power and authority to execute and deliver
this Agreement and to consummate the transactions contemplated hereby. The
execution and delivery of this Agreement and the consummation of the
transactions contemplated hereby by the Company have been duly authorized by all
necessary corporate action on the part of the Company. This Agreement has been
duly executed and delivered by the Company and, assuming its due authorization,
execution and delivery by the Stockholders, constitutes a legal, valid and
binding obligation of the Company, enforceable against the Company in accordance
with its terms.

     SECTION 3.02  No Conflict; Required Filings and Consents. (a) The execution
and delivery of this Agreement by the Company do not, and the performance of
this Agreement by the Company will not, (i) conflict with or violate the
Articles of Incorporation or By-laws of the Company, (ii) conflict with or
violate any law, rule, regulation, order, judgment or decree applicable to the
Company or by which the Company or any of its properties is bound or affected,
or (iii) result in any breach of or constitute a default (or an event that with
notice or lapse of time or both would become a default) under, or give to others
any rights of termination, amendment, acceleration or cancellation of, or result
in the creation of a lien or encumbrance on any of the property or assets of the
Company pursuant to, any note, bond, mortgage, indenture, contract, agreement,
lease, license, permit, franchise or other instrument or obligation to which the
Company is a party or by which it or any of its properties is bound or affected,
except for any such breaches, defaults or other occurrences that would not cause
or create a material risk of non-performance or delayed performance by the
Company of its obligations under this Agreement.

     (b) The execution and delivery of this Agreement by the Company do not, and
the performance of this Agreement by the Company will not, require any consent,
approval, authorization or permit of, or filing with or notification to, any
governmental or regulatory authority, domestic or foreign, except (i) for
applicable requirements, if any, of the Exchange Act and the HSR Act and (ii)
where the failure to obtain such consents, approvals, authorizations or permits,
or to make such filings or notifications, would not prevent or delay the
performance by the Company of its obligations under this Agreement.

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                                   ARTICLE IV

                               GENERAL PROVISIONS

     SECTION 4.01  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 delivered, mailed or transmitted, and shall be effective
upon receipt, if delivered personally, mailed by registered or certified mail
(postage prepaid, return receipt requested) to the parties at the following
addresses (or at such other address for a party as shall be specified by like
changes of address) or sent by electronic transmission to the telecopier number
specified below:

     (a) If to the Company

         Eltrax Systems, Inc.
         400 Galleria Parkway, Suite 300
         Atlanta, Georgia 30339
         Attention: Chief Executive Officer
         Telecopier No.: (678) 589-3570

     with a copy to:

         Jaffe, Raitt, Heuer & Weiss, Professional Corporation
         One Woodward Avenue
         Suite 2400
         Detroit, Michigan 48226
         Attention: William E. Sider, Esq.
         Telecopier No.: (313) 961-8358

     (b) If to a Stockholder, to such Stockholder's address set forth on Exhibit
A.

     SECTION 4.02  Headings. The headings contained in this Agreement are for
reference purposes only and shall not affect in any way the meaning or
interpretation of this Agreement.

     SECTION 4.03  Severability. If any term or other provision of this
Agreement is invalid, illegal or incapable of being enforced by any rule of law
or public policy, all other conditions and provisions of this Agreement shall
nevertheless remain in full force and effect so long as the economic or legal
substance of the transactions contemplated hereby is not affected in any manner
materially adverse to any party. Upon such determination that any term or other
provision is invalid, illegal or incapable of being enforced, the parties hereto
shall negotiate in good faith to modify this Agreement so as to effect the
original intent of the parties as closely as possible to the fullest extent
permitted by applicable law in an acceptable manner to the end that the
transactions contemplated hereby are fulfilled to the extent possible.

     SECTION 4.04  Entire Agreement. This Agreement constitutes the entire
agreement of the parties and supersedes all prior agreements and undertakings,
both written and oral, between the parties, or any of them, with respect to the
subject matter hereof.

     SECTION 4.05  Assignment. This Agreement shall not be assigned by operation
of law or otherwise; provided, however, that the Company may assign its rights,
interests and obligations hereunder to any successor or parent entity of the
Company whose shares are registered under Section 12 of the Exchange Act (or
will be so registered at the Closing).

     SECTION 4.06  Parties in Interest. This Agreement shall be binding upon and
inure solely to the benefit of each party hereto, and nothing in this Agreement,
express or implied, is intended to or shall confer upon any person any right,
benefit or remedy of any nature whatsoever under or by reason of this Agreement.

     SECTION 4.07  Specific Performance. The parties hereto agree that
irreparable damage would occur in the event any provision of this Agreement was
not performed in accordance with the terms hereof and

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that the parties shall be entitled to specific performance of the terms hereof,
in addition to any other remedy at law or in equity.

     SECTION 4.08  Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF DELAWARE APPLICABLE TO
CONTRACTS EXECUTED AND TO BE PERFORMED ENTIRELY WITHIN THAT STATE. COMPANY AND
EACH OF THE STOCKHOLDERS EACH HEREBY IRREVOCABLY SUBMITS TO THE JURISDICTION OF
ANY GEORGIA STATE OR FEDERAL COURT SITTING IN THE CITY OF ATLANTA, GEORGIA, IN
ANY ACTION OR PROCEEDING ARISING OUT OF OR RELATING TO THIS AGREEMENT, AND
COMPANY AND EACH OF THE STOCKHOLDERS HEREBY IRREVOCABLY AGREES THAT ALL CLAIMS
IN RESPECT OF SUCH ACTION OR PROCEEDING MAY BE HEARD AND DETERMINED IN SUCH
GEORGIA STATE COURT OR SUCH FEDERAL COURT. THE COMPANY AND EACH OF THE
STOCKHOLDERS EACH HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT IT MAY
EFFECTIVELY DO SO, THE DEFENSE OF AN INCONVENIENT FORUM TO THE MAINTENANCE OF
SUCH ACTION OR PROCEEDING.

     SECTION 4.09  Counterparts. This Agreement may be executed in one or more
counterparts, and by the different parties hereto in separate counterparts, each
of which when executed shall be deemed to be an original but all of which taken
together shall constitute one and the same agreement.

     IN WITNESS WHEREOF, the parties have executed and delivered this Agreement
or caused this Agreement to be executed and delivered by its duly authorized
officer, all as of the date first written above.

                                            ELTRAX SYSTEMS, INC.

                                            By:   /s/ WILLIAM P. O'REILLY
                                              ----------------------------------
                                                Name: William P. O'Reilly
                                                Title:  Chairman

                                            STOCKHOLDERS:

                                                   /s/ STEVEN A. ODOM
                                            ------------------------------------
                                                       STEVEN A. ODOM

                                                   /s/ AMY L. NEWMARK
                                            ------------------------------------
                                                       AMY L. NEWMARK

                                                  /s/ JAMES M. LOGSDON
                                            ------------------------------------
                                                      JAMES M. LOGSDON

                                                /s/ JOSEPH W. WRIGHT, JR.
                                            ------------------------------------
                                                   JOSEPH W. WRIGHT, JR.

                                                    /s/ GARY H. HECK
                                            ------------------------------------
                                                        GARY H. HECK

                                                  /s/ JULIET M. REISING
                                            ------------------------------------
                                                     JULIET M. REISING

                                                   /s/ MAX E. BOBBITT
                                            ------------------------------------
                                                       MAX E. BOBBITT
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                                                                       EXHIBIT A

                              LIST OF STOCKHOLDERS

<TABLE>
<CAPTION>
                                                                NUMBER OF SHARES
                                                                   OF COMPANY
                                                                  COMMON STOCK
                                                               OWNED BENEFICIALLY
NAME AND ADDRESS OF STOCKHOLDER                                  AND OF RECORD
-------------------------------                                ------------------
<S>                                                            <C>
Steven A. Odom..............................................        675,825
  Cereus Technology Partners, Inc.
  400 Northpark, Suite 1000
  1000 Abernathy Road
  Atlanta, Georgia 30328
Amy L. Newmark..............................................        250,000
  21 Hedgerow Lane
  Greenwich, Connecticut 06831
James M. Logsdon............................................        205,000
  Cereus Technology Partners, Inc.
  400 Northpark, Suite 1000
  1000 Abernathy Road
  Atlanta, Georgia 30328
Joseph W. Wright, Jr. ......................................        158,414
  599 Lexington Avenue, 44th Floor
  New York, NY 10022
Gary H. Heck................................................         75,000
  19638 Painted Ridge Loop
  Bend, Oregon 97702
Juliet M. Reising...........................................         55,000
  Cereus Technology Partners, Inc.
  400 Northpark, Suite 1000
  1000 Abernathy Road
  Atlanta, Georgia 30328
Max E. Bobbitt..............................................         50,000
  70 Beachside Drive, Apt. 203
  Vero Beach, Florida 32963
</TABLE>