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                                   EXHIBIT 4.2

                                    AMENDMENT
                                       TO
                              HYCOR BIOMEDICAL INC.
                         NONQUALIFIED STOCK OPTION PLAN
                           FOR NON-EMPLOYEE DIRECTORS

         This Amendment to Hycor Biomedical Inc. Nonqualified Stock Option Plan
for Non-Employee Directors (the "Amendment") is dated effective as of June 10,
1998.

         WHEREAS, Hycor Biomedical Inc. (the "Company") adopted and the
stockholders approved the Company's Nonqualified Stock Option Plan for
Non-Employee Directors (the "Plan") pursuant to which options can be granted by
the Company to non-employee directors of the Company.

         WHEREAS, pursuant to Section 7 of the Plan the Company's Board of
Directors has validly taken action to amend the Plan.

         WHEREAS, pursuant to Section 7 of the Plan the stockholders of the
Company have approved the Amendment at the Annual Meeting of Stockholders on
June 10, 1998.

         NOW THEREFORE, the Plan is amended as follows:

         1. Amendment to Section 2. The number of shares that may be issued or
transferred and sold pursuant to the Plan is hereby amended to read in its
entirety as follows:

         "325,000"

         To record the valid adoption of this Amendment by the Board of
Directors and valid approval of this Amendment by the stockholders of the
Company as of June 10, 1998, the Company has caused its authorized officers to
execute this Amendment on behalf of the Company.

                                        Hycor Biomedical Inc.

                                        By:    /s/ J. David Tholen
                                           -------------------------------------
                                               J. David Tholen
                                        Title: President and
                                               Chief Executive Officer

                                        By:    /s/ Reginald P. Jones
                                           -------------------------------------
                                               Reginald P. Jones
                                        Title: Senior Vice President and
                                               Chief Financial OfficerEXHIBIT 10.1

July 21, 2000

   Wiskers Acquisition Corporation
   87 Sea Holly Way

   Suite 2000
   Henderson, NV 89014

    Re:   Shareholder Agreement with Wiskers Acquisition Corporation

   Gentlemen:

    In  consideration  of the sale of the  shares  of  Common  Stock of  Wiskers
Acquisition Corporation (the "Company") to the undersigned (the "Holders"),  the
Holders hereby represent, warrants, covenants and agrees, for the benefit of the
Company  and any  holders of record (the  "third  party  beneficiaries")  of the
Company's  outstanding  securities,  including the Company's Common Stock, $.001
par value (the  "Stock")  at the date  hereof and  during the  pendency  of this
letter agreement,  that the Holders will not transfer,  sell,  contract to sell,
devise,  gift, assign,  pledge,  hypothecate,  distribute or grant any option to
purchase or otherwise dispose of, directly or indirectly, its shares of Stock of
the Company owned  beneficially or otherwise by the Holders except in connection
with or following completion of a merger, acquisition or other transaction of or
by the Company  meeting the  definition of a business  combination as defined in
the Company's  registration  statement on Form 10-SB or otherwise complying with
the purposes of the Company as set out in the registration statement.

          Any attempted sale, transfer or other disposition in violation of this
letter agreement shall be null and void.

    The Holder  further  agrees that the Company (i) may  instruct  its transfer
agent not to  transfer  such  securities  (ii) may provide a copy of this letter
agreement to the Company's  transfer  agent for the purpose of  instructing  the
Company's transfer agent to place a legend on the certificate(s)  evidencing the
securities subject hereto and disclosing that any transfer,  sale,  contract for
sale, devise,  gift,  assignment,  pledge or hypothecation of such securities is
subject to the terms of this letter agreement and (iii) may issue  stop-transfer
instructions  to its transfer agent for the period  contemplated  by this letter
agreement for such securities.

    This letter agreement shall be binding upon the Holders, its agents,  heirs,
successors, assigns and beneficiaries.

    Any waiver by the Company of any of the terms and  conditions of this letter
agreement in any instance  shall be in writing and shall be duly executed by the
Company  and the Holder and shall not be deemed or  construed  to be a waiver of
such term or condition for the future, or of any subsequent breach thereof.

          Agreed and accepted this 21st day of July, 2000.

                        THE HOLDER

                                 By: _____________________________
                                      PresidentEXHIBIT 10.1

March 27 2000

DALJAMA, INC.
1353 Middleton Dr.
Cedar Hill, Texas 75104

    Re:   Shareholder Agreement with Daljama, Inc.

   Gentlemen:

    In consideration of the sale of the shares of Common Stock of Daljama,  Inc.
(the  "Company")  to  the  undersigned  (the  "Holders"),   the  Holders  hereby
represent,  warrants,  covenants and agrees,  for the benefit of the Company and
any  holders  of record  (the  "third  party  beneficiaries")  of the  Company's
outstanding  securities,  including the Company's Common Stock,  $.001 par value
(the  "Stock")  at the date  hereof  and  during  the  pendency  of this  letter
agreement,  that the Holders will not transfer,  sell, contract to sell, devise,
gift, assign, pledge, hypothecate, distribute or grant any option to purchase or
otherwise dispose of, directly or indirectly, its shares of Stock of the Company
owned  beneficially  or otherwise by the Holders  except in  connection  with or
following completion of a merger,  acquisition or other transaction of or by the
Company  meeting  the  definition  of a business  combination  as defined in the
Company's  registration  statement on Form 10-SB or otherwise complying with the
purposes of the Company as set out in the registration statement.

          Any attempted sale, transfer or other disposition in violation of this
letter agreement shall be null and void.

    The Holder  further  agrees that the Company (i) may  instruct  its transfer
agent not to  transfer  such  securities  (ii) may provide a copy of this letter
agreement to the Company's  transfer  agent for the purpose of  instructing  the
Company's transfer agent to place a legend on the certificate(s)  evidencing the
securities subject hereto and disclosing that any transfer,  sale,  contract for
sale, devise,  gift,  assignment,  pledge or hypothecation of such securities is
subject to the terms of this letter agreement and (iii) may issue  stop-transfer
instructions  to its transfer agent for the period  contemplated  by this letter
agreement for such securities.

    This letter agreement shall be binding upon the Holders, its agents,  heirs,
successors, assigns and beneficiaries.

    Any waiver by the Company of any of the terms and  conditions of this letter
agreement in any instance  shall be in writing and shall be duly executed by the
Company  and the Holder and shall not be deemed or  construed  to be a waiver of
such term or condition for the future, or of any subsequent breach thereof.

          Agreed and accepted this 27th day of March, 2000.

                        THE HOLDER

                                 By: _________________________
                                      PresidentExhibit 4.3
                 NOTE LEGEND ON REVERSE SIDE OF THIS CERTIFICATE

                           INCORPORATED UNDER THE LAWS
                            OF THE STATE OF DELAWARE

Certificate Number                                         Shares
    - 0 -                                                   - 0 -
                                                       CUSIP 40636X 10 5
 COMMON STOCK                                SEE REVERSE FOR CERTAIN DEFINITIONS

                           HALLWOOD ENERGY CORPORATION

         THIS CERTIFIES that    ------------ S P E C I M E N--------------

         is the owner of    ------------------ 0 -------------------------------

             FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK OF
                       THE PAR VALUE OF $.01 PER SHARE, OF

                           HALLWOOD ENERGY CORPORATION

         transferable  on the books of the  Corporation  by the holder hereof in
         person  or  by  duly  authorized  attorney,   upon  surrender  of  this
         certificate  properly  endorsed.  This  certificate is not valid unless
         countersigned by the Transfer Agent and registered by the Registrar.

       Witness the seal of the Corporation and the signatures of its duly
       authorized officers.

           Dated: -----------------

/s/ William L. Guzzetti                                   /s/ Cathleen M. Osborn
------------------------                                  ----------------------
President                                                 Secretary

<PAGE>

                           HALLWOOD ENERGY CORPORATION

         The  Corporation  will furnish upon request and without  charge to each
  stockholder the powers, designations, preferences and relative, participating,
  optional and other  special  rights of each class of stock and series within a
  class of stock of the Corporation, as well as the qualifications,  limitations
  and restrictions  relating to those  preferences  and/or rights. A stockholder
  may  make  the  request  to the  Corporation  or to  its  Transfer  Agent  and
  Registrar.

         This  certificate  also evidences and entitles the holder hereof to the
  same number of Rights as the number of Shares represented by this certificate,
  such Rights being on the terms  provided  under the Rights  Agreement  between
  Hallwood  Energy  Corporation  and Registrar and Transfer  Company,  as rights
  agent (the "Rights  Agent") (the "Rights  Agreement"),  the terms of which are
  incorporated  herein  by  reference  and a copy  of  which  is on  file at the
  principal  executive  offices of Hallwood  Energy  Corporation.  Under certain
  circumstances,  as set forth in the Rights  Agreement,  such  Rights  shall be
  evidenced  by separate  certificates  and shall no longer be evidenced by this
  certificate.  Hallwood Energy  Corporation shall mail to the registered holder
  of this certificate a copy of the Rights Agreement  without charge within five
  days after receipt of a written request therefor.  Under certain circumstances
  as provided in the Rights  Agreement,  Rights  issued to or owned by Acquiring
  Persons or their Affiliates or Associates (as defined in the Rights Agreement)
  and any subsequent holder of such Rights shall be null and void.

         The following  abbreviations,  when used in the inscription on the face
  of this  certificate,  shall be  construed  as though they were written out in
  full according to applicable laws or regulations:

 TEN COM -  as tenants in common     UNIF GIFT MIN ACT -- ---- Custodian -----
 TEN ENT -  as tenants by the entireties                 (Cust)         (Minor)
 JT TEN  -  as joint tenants with right of         under Uniform Gifts to Minors
            survivorship and not as tenants        Act ------------------
            in common                                      (State)

     Additional abbreviations may also be used though not in the above list.

         For  value  received,   -------------------  hereby  sell,  assign  and
  transfer unto PLEASE INSERT SOCIAL SECURITY OR OTHER
        IDENTIFYING NUMBER OF ASSIGNEE
   ----------------------------------------

---------- ------------- --------------------------- ---------------------------

PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS INCLUDING POSTAL ZIP CODE OF ASSIGNEE

-------------------------------------------------------------------------Shares

represented by the within Certificate, and do hereby irrevocably constitute and
appoint-------------------------------------------------------------------------

  Attorney  to  transfer  the  said  shares  on the  books  of the  within-named
  Corporation with full power of substitution in the premises.

  Dated, --------------------

                                                     X--------------------------
                                                             (SIGNATURE)
NOTICE:

THE SIGNATURE(S) TO THIS ASSIGNMENT MUST
CORRESPOND WITH THE NAME(S) AS WRITTEN
UPON THE FACE OF THE CERTIFICATE IN EVERY
PARTICULAR WITHOUT ALTERATION OR ENLARGEMENT
OR ANY CHANGE WHATEVER.
                                                     X--------------------------
                                                              (SIGNATURE)

  THESE SHARES HAVE NOT BEEN REGISTERED  UNDER THE SECURITIES ACT OF 1933 OR ANY
  APPLICABLE STATE LAW. THEY MAY NOT BE OFFERED FOR SALE,  SOLD,  TRANSFERRED OR
  PLEDGED  WITHOUT (1)  REGISTRATION  UNDER THE  SECURITIES  ACT OF 1933 AND ANY
  APPLICABLE  STATE LAW,  OR (2) AN OPINION  (SATISFACTORY  TO THE  COMPANY)  OF
  COUNSEL THAT REGISTRATION IS NOT REQUIRED.

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