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                                                                    EXHIBIT 10.6

                            CASCO INTERNATIONAL, INC.
                         1997 EMPLOYEE STOCK OPTION PLAN


SECTION 1 - PURPOSE:

1.1      The purpose of this Employee Stock Option Plan ("Plan") is to further
         the success of CASCO International, Inc., a Delaware corporation
         ("Company") by making available Common Stock of the Company for
         purchase by certain officers and employees of the Company and its
         affiliates, and thus to provide an additional incentive to such
         individuals to continue in the service of the Company or its affiliates
         and to give them a greater interest as Stockholders in the success of
         the Company. Subject to compliance with the provisions of the Plan and
         the Internal Revenue Code of 1986, as amended, Incentive Stock Options
         as authorized by Section 422 of the Code and stock options which do not
         qualify under Section 422 of the Code are authorized and may be granted
         under the Plan.

SECTION 2 - DEFINITIONS:

2.1      As used in this Plan, the following terms shall have the meanings
         indicated as follows:

         2.1.1    "Board" means the Board of Directors of the Company.

         2.1.2    "Code" means the Internal Revenue Code of 1986, as amended.

         2.1.3    "Committee" means the Committee administering the Plan
                  described in Section 3 hereof.

         2.1.4    "Common Stock" means the Company's Common Stock, par value
                  $.01 per share.

         2.1.5    "Date of Grant" means the date on which an option is granted
                  under a written option agreement executed by the Company and a
                  Participant pursuant to the Plan.

         2.1.6    "Effective Date" means the effective date of this Plan
                  specified in Paragraph 13 hereof.

         2.1.7    "Exchange Act" means the Securities Exchange Act of 1934, as
                  it may be amended from time to time.

         2.1.8    "Incentive Stock Option" means an option qualifying under
                  Section 422 of the Code.

         2.1.9    "Non-Employee Director" means a person who meets the
                  definition of a "non-Employee Director" as defined in Rule
                  16b-3 promulgated under the Exchange Act or any successor
                  provision.

         2.1.10   "Parent" means a parent corporation of the Company as defined
                  in Section 424(e) of the Code.

         2.1.11   "Participants" means the employees and officers of the
                  Company, its Subsidiaries and



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                  its Parents, and those directors of the Company who are also
                  employees of the Company, its subsidiaries or its Parents.

         2.1.12   "Subsidiary" means a subsidiary corporation of the Company as
                  defined in Section 424(f) of the Code.

SECTION 3 - ADMINISTRATION OF THE PLAN:

3.1      The Board of Directors of the Company shall appoint a committee
         ("Committee") comprised of two (2) or more directors to administer the
         Plan. Only directors who are Non-Employee Directors shall be eligible
         to serve as members of the Committee. The Committee shall report all
         action taken by it to the Board which shall review and ratify or
         approve those actions that are, by law, required to be so reviewed and
         ratified or approved by the Board. The Committee shall have full and
         final authority in its discretion, subject to the provisions of the
         Plan, to determine the Participants to whom, and the time or times at
         which options shall be granted and the number of shares and purchase
         price of Common Stock covered by each option; to construe and interpret
         the Plan and any agreements made pursuant to the Plan; to determine the
         terms and provisions (which need not be identical or consistent with
         respect to each Participant) of the respective option agreements and
         any agreement ancillary thereto including, but without limitation,
         terms covering the payment of the option price; and to make all other
         determinations and to take all other actions deemed necessary or
         advisable for the proper administration of the Plan. All such actions
         and determinations shall be conclusively binding for all purposes and
         upon all persons.

SECTION 4 - OPTIONS AUTHORIZED:

4.1      The options granted under this Plan may be Incentive Stock Options or
         stock options that do not qualify as Incentive Stock Options (sometimes
         referred to as "non-qualified options" or "non-qualified stock
         options"). The Committee shall have the full power and authority to
         determine which options shall be non-qualified stock options and which
         shall be Incentive Stock Options; to grant only Incentive Stock Options
         or, alternatively, only non-qualified stock options; and to, in its
         sole discretion, grant to the holder of an outstanding option in
         exchange for the surrender and cancellation of such option, a new
         option having purchase price lower than that provided in the option so
         surrendered and cancelled and containing such other terms and
         conditions as the Committee may prescribe in accordance with the
         provisions of the Plan. No options may be granted under the Plan prior
         to the Effective Date. In addition to any other limitations set forth
         herein, the aggregate fair market value, determined in accordance with
         Paragraph 7(A) of the Plan as of the time the option is granted, of the
         stock with respect to which Incentive Stock Options are exercisable for
         the first time by a Participant in any calendar year (under all plans
         of the Company and of any Parent or Subsidiary) shall not exceed
         $100,000.

SECTION 5 - COMMON STOCK SUBJECT TO OPTIONS:

5.1      The aggregate number of shares of the Company's Common Stock which may
         be issued upon the exercise of options shall not exceed one hundred
         fifty thousand (150,000), subject to adjustment under the provisions of
         Paragraph 8. The shares of Common Stock to be issued upon the exercise
         of options may be authorized but unissued shares, or shares issued



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         and reacquired by the Company. In the event any option shall, for any
         reason, terminate or expire or be surrendered without having been
         exercised in full, the shares subject to such option shall again be
         available for options to be granted under the Plan, except that shares
         for which relinquished options (or portions thereof) are exercisable
         shall not again be available for options under the Plan.

SECTION 6 - PARTICIPANTS:

6.1      Except as hereinafter provided, options may be granted under the Plan
         to any Participant. In determining the Participants to whom options
         shall be granted and the number of shares to be covered by such option,
         the Committee may take into account the nature of the services rendered
         by the respective Participants, their present and potential
         contributions to the Company's success, and such other factors as the
         Committee, in its discretion, shall deem relevant. A participant who
         has been granted an option under the Plan may be granted an additional
         option(s) under the Plan, in the Committee's discretion.

SECTION 7 - TERMS AND CONDITIONS OF OPTIONS:

7.1      The grant of an option under the Plan shall be evidenced by a written
         agreement executed by the Company and the applicable participant and
         shall contain such terms and be in such form as the Committee may, from
         time to time, approve, subject to the following limitations and
         conditions:

         7.1.1    OPTION PRICE: The option price per share with respect to each
                  option shall be determined by the Committee, but shall in no
                  instance be less than the par value of the shares subject to
                  the option. In addition, the option price per share with
                  respect to Incentive Stock Options granted hereunder shall in
                  no instance be less than the fair market value of the shares
                  of Common Stock subject to the option as determined by the
                  Committee. The Committee shall, in good faith, determine the
                  fair market value of the shares of Common Stock (without
                  regard to any restrictions other than a restriction which, by
                  its terms, will never lapse) based upon a reasonable method of
                  valuation adopted by the Committee, or such other method as
                  may be permitted by the Code, or regulations or rulings
                  promulgated thereunder. The Committee may permit the option
                  purchase price to be payable by any of the following means or
                  any combination thereof: (i) cash; (ii) certified or cashier's
                  check payable to the Company; (iii) the delivery of whole
                  shares of Common Stock owned by the Option holder; or (iv) by
                  requesting that the Company withhold whole shares of Common
                  Stock then issuable upon exercise of the Option (for purposes
                  of such a transaction the value of the shares of Common Stock
                  shall be deemed to be equal to the fair market value, as
                  determined by the Committee in good faith, of the shares on
                  the date of the exercise of the Option) in which case the
                  Option with respect to the shares withheld shall be deemed to
                  be surrendered and cancelled.

         7.1.2    PERIOD OF OPTION: The expiration date of each option shall be
                  fixed by the Committee but, notwithstanding any provision of
                  the Plan to the contrary, such expiration date shall not be
                  more than five (5) years after the Date of Grant.

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         7.1.3      VESTING OF STOCKHOLDER RIGHTS: Neither the optionee nor
                    his/her successor in interest shall have any of the rights
                    of a Stockholder of the Company until the shares relating to
                    the option hereunder are issued by the Company and are
                    properly delivered to such optionee or successor.

         7.1.4      EXERCISE OF OPTION: Each option shall be exercisable from
                    time to time, but not less than six (6) months after the
                    Date of Grant, over such period and upon such terms and
                    conditions as the Committee shall determine, but not at any
                    time as to less than twenty-five (25) shares unless the
                    remaining shares which have become so purchasable are less
                    than twenty-five (25) shares. After the death of the
                    optionee, an option may be exercised as provided in
                    Paragraph 15 hereof.

         7.1.5      NON-TRANSFERABILITY OF OPTION: No option shall be
                    transferable or assignable by an optionee, other than by
                    will or the laws of descent and distribution or pursuant to
                    a qualified domestic relations order and each option shall
                    be exercisable, during the optionee's lifetime, only by
                    him/her or, during periods of legal disability, by his/her
                    legal representative. No option shall be subject to
                    execution, attachment, or similar process.

         7.1.6      DISQUALIFYING DISPOSITION: The option agreement evidencing
                    any Incentive Stock Options granted under this Plan shall
                    provide that if the optionee makes a disposition, within the
                    meaning of Section 424(c) of the Code and regulations
                    promulgated thereunder, of any share(s) of Common Stock
                    issued to him/her pursuant to exercise of the option within
                    the two (2) year period commencing on the day after the date
                    of issuance of the share(s) to him/her pursuant to the
                    exercise of such option, he/she shall, within ten (10) days
                    after such disposition date, notify the company of the sales
                    price or other value ascribed to or used to measure the
                    disposition of the share(s) thereof and immediately deliver
                    to the Company any amount of federal income tax withholding
                    required by law.

         7.1.7      LIMITATION ON GRANTS TO CERTAIN STOCKHOLDERS: An Incentive
                    Stock Option may be granted to a participant only if such
                    Participant, at the time the option is granted, does not
                    own, after application of the attribution rules of Code
                    Section 424, stock possessing more than ten percent (10%) of
                    the total combined voting power of all classes of Common
                    Stock of the company or of its parent or Subsidiary. The
                    preceding restriction shall not apply if at the time the
                    option is granted, the option price is at least one hundred
                    ten percent (110%) of the fair market value, as defined in
                    Paragraph 7(A) above, of the common Stock subject to the
                    option and such option by its terms is not exercisable after
                    the expiration of five (5) years after the Date of Grant.

         7.1.8      CONSISTENCY WITH CODE: Notwithstanding any other provision
                    in this Plan to the contrary, the provisions of all
                    agreements granting incentive stock options pursuant to the
                    Plan shall not violate the requirements of the Code
                    applicable to the Incentive Stock Options authorized
                    hereunder.


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SECTION 8 - ADJUSTMENTS:

8.1      The Committee, in its discretion, may make such adjustments in the
         option price and the number of shares covered by outstanding options
         that are required to prevent any dilution or enlargement of the rights
         of the holders of such options that would otherwise result from any
         reorganization, recapitalization, stock split, stock dividend,
         combination of shares, merger, consolidation, issuance of rights, or
         any other change in the capital structure of the Company. The
         Committee, in its discretion, may also make such adjustments in the
         aggregate number of shares that may be the subject of options which are
         appropriate to reflect any transaction or event described in the
         preceding sentence.

SECTION 9 - RESTRICTION OF ISSUING SHARES:

9.1      The exercise of each option shall be subject to the condition that if
         at any time the company shall determine, in its discretion, that the
         satisfaction of withholding tax or other withholding liabilities, or
         that the listing, registration, or qualification of any shares
         otherwise deliverable upon such exercise upon any securities exchange
         or under any state or federal law, or that the consent or approval of
         any regulatory body is necessary or desirable as a condition of, or in
         connection with, such exercise or the delivery or purchase of shares
         pursuant thereto, then in any such event, such exercise shall not be
         effective unless such withholding, listing, registration,
         qualification, consent, or approval shall have been effected or
         obtained free of any conditions not acceptable to the Company.

SECTION 10 - USE OF PROCEEDS:

10.1     The proceeds received by the Company from the sale of Common Stock
         pursuant to the exercise of options granted under the Plan shall be
         added to the Company's general funds and used for general corporate
         purposes.

SECTION 11 - AMENDMENT, SUSPENSION, AND TERMINATION OF PLAN:

11.1     The Board may, at any time, suspend or terminate the Plan or may amend
         it from time to time in such respects as the Board may deem advisable
         in order that the options granted thereunder may conform to any changes
         in the law or in any other respect that the Board may deem to be in the
         best interests of the Company provided, however, that without approval
         by the Stockholders of the Company voting the proper percentage of its
         voting power, no such amendment shall make any change in the Plan for
         which Stockholder approval is required of the Company in order to
         comply with:

         11.1.1   The Code or regulatory provisions dealing with Incentive Stock
                  Options;

         11.1.2   Any rules for listed companies promulgated by any national
                  stock exchange on which the Company's stock is traded; or

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         11.1.3     Any other applicable rule of law.

11.2     Unless sooner terminated hereunder, the Plan shall terminate ten (10)
         years after the Effective Date. No option may be granted during any
         suspension or after the termination of the Plan. Except as provided in
         Paragraph 12, no amendment, suspension, or termination of the Plan
         shall, without an optionee's consent, impair or negate any of the
         rights or obligations under any option theretofore granted to such
         optionee under the Plan.

SECTION 12 - TAX WITHHOLDING:

12.1 The Committee may, in its sole discretion:

         12.1.1   Require an optionee to remit to the Company a cash amount
                  sufficient to satisfy, in whole or in part, any federal,
                  state, or local withholding tax requirements prior to the
                  delivery of any certificate for shares pursuant to the
                  exercise of an option hereunder; or,

         12.1.2   Satisfy such withholding requirements through another lawful
                  method.

SECTION 13 - EFFECTIVE DATE OF PLAN:

13.1     This Plan shall become effective (the "Effective Date") upon adoption
         by the Board, and in the case of Incentive Stock Options, subject to
         approval within twelve (12) months after such adoption by holders of a
         majority of the shares of Common Stock present in person or by proxy
         and entitled to vote at a duly held Stockholders meeting. Options,
         including Incentive Stock Options, may be granted under the Plan prior
         to the receipt of such approval.

SECTION 14 - TERMINATION OF EMPLOYMENT:

14.1     In the event of the retirement, with the written consent of the
         Company, or other termination of the employment of an employee to whom
         an option has been granted under the Plan other than:

         14.1.1   A termination that is either (i) for cause or (ii) voluntary
                  on the part of the employee and without the written consent of
                  the Company; or,

         14.1.2   A termination by reason of death.

14.2     The employee may, unless otherwise provided in his/her option
         agreement, exercise his/her option at any time within three (3) months
         after such retirement or other termination of employment (or within one
         (1) year after termination of employment due to disability within the
         meaning of Code Section 422(c)(6), or within such other time as the
         Committee shall authorize, but in no event after five (5) years after
         the date of granting thereof, or such lesser period as may be specified
         in the stock option agreement), but only to the extent of the number of
         shares of which his/her options were exercisable by him/her at the date
         of the termination of his/her employment.

14.3     In the event of the termination of the employment of an employee to
         whom an option has



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         been granted under the Plan that is either for cause, or voluntary on
         the part of the employee and without the written consent of the
         company, any option held by him/her under the Plan, to the extent not
         previously exercised, shall forthwith terminate on the date of such
         termination of employment. Options granted under the Plan shall not be
         affected by any change of employment so long as the holder continues to
         be an employee of the Company, a Subsidiary, or Parent. The option
         agreement may contain such provisions as the Committee shall approve
         with respect to the effect of approved leaves of absence. Nothing in
         the Plan, or in any option granted pursuant to the Plan, shall confer
         on any individual any right to continue in the employ of the Company or
         any of its Subsidiaries or Parents, or interfere in any way with the
         right of the Company or any of its Subsidiaries or Parents to terminate
         his employment at any time.

SECTION 15 - DEATH OF HOLDER OF OPTION:

15.1     In the event an employee to whom an option has been granted under the
         Plan dies during or within three (3) months after the termination of
         his/her employment by the Company or a subsidiary or Parent, such
         option, unless it shall have been previously terminated pursuant to the
         provision of the Plan, or unless otherwise provided in his/her option
         agreement, may be exercised to the extent of the entire number of
         shares covered by the option whether or not purchasable by the employee
         at the date of his/her death, by the executor or administrator of the
         optionee's estate or by the person(s) to whom the optionee shall have
         transferred such option by will or by the laws of descent and
         distribution, at any time within a period of one (1) year after this
         death, but not after the exercise termination date set forth in the
         relevant stock option agreement.

SECTION 16 - LOANS TO ASSIST IN EXERCISE OF OPTIONS:

16.1     If approved by the Board, the Company or any Parent or Subsidiary may
         lend money or guarantee loans by third parties to an individual to
         finance the exercise of any option granted under the Plan to carry
         Common Stock thereby acquired. No such loans to finance the exercise of
         an Incentive Stock Option shall have an interest rate or other terms
         that would cause any part of the principal amount to be characterized
         as interest for purpose of the Code.

SECTION 17 - RULE 16b-3 PLAN:

17.1     This Plan is intended and has been drafted to comply in all respects
         with Rule 16b-3, as amended, under the Exchange Act. If any provision
         of this Plan does not comply with Rule 16b-3, as amended, this Plan
         shall be automatically amended to comply with Rule 16b-3, as amended.

SECTION 18 - INDEMNIFICATION:

18.1     The members of the Committee shall be indemnified by the Corporation
         against the reasonable expenses incurred in connection with the defense
         of any action, suit or proceeding, or in connection with any appeal
         thereof, to which they or any of them may be a party by reason of any
         action taken or failure to act under or in connection with the Plan or
         any Option, and against all amounts paid by them in settlement thereof
         (provided such settlement is approved by legal counsel selected by the
         Corporation) or paid by them in



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         satisfaction of a judgment in any such action, suit or proceeding. A
         member of the Committee shall not be entitled to indemnification with
         respect to any matter or claim arising out of gross negligence or
         willful misconduct by such member in the performance of his duties. As
         a condition of any indemnification, a Committee member shall in writing
         offer the Corporation the opportunity, at its own expense, to handle
         and defend any suit or claim against him/her.



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