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                                                                     EXHIBIT 4.2

                                 ST LABS, INC.
                             1997 STOCK OPTION PLAN

This 1997 Stock Option Plan (the "Plan") provides for the grant of options to
acquire shares of Common Stock, without par value (the "Common Stock"), of ST
Labs, Inc., a Washington corporation (the "Company"). Stock options granted
under this Plan that qualify under Section 422 of the Internal Revenue Code of
1986, as amended (the "Code"), are referred to in this Plan as "Incentive Stock
Options." Incentive Stock Options and stock options that do not qualify under
Section 422 of the Code ("Non-Qualified Stock Options") granted under this Plan
are referred to collectively as "Options."

1. PURPOSES.
The purposes of this Plan are to retain the services of valued key employees and
consultants of the Company and such other persons as the Plan Administrator
shall select in accordance with Section 3 below, to encourage such persons to
acquire a greater proprietary interest in the Company, thereby strengthening
their incentive to achieve the objectives of the shareholders of the Company,
and to serve as an aid and inducement in the hiring of new employees and
consultants.

2. ADMINISTRATION.
This Plan shall be administered by the Board of Directors of the Company (the
"Board"), except that the Board may, in its discretion, establish a committee
composed of members of the Board or other persons to administer this Plan,
which committee (the "Committee") may be an executive, compensation or other
committee, including a separate committee especially created for this purpose.
The Committee shall have such of the powers and authority vested in the Board
hereunder as the Board may delegate to it (including the power and authority to
interpret any provision of this Plan or of any Option). The members of any such
Committee shall serve at the pleasure of the Board. The Board and/or the
Committee if one has been established by the Board, are referred to in this
Plan as the "Plan Administrator."

In the event the Company registers any of its equity securities pursuant to
Section 12(b) or 12(g) of the Securities Exchange Act of 1934, as amended (the
"Exchange Act"), it is the intention of the Company that this Plan, and options
granted under this Plan, comply in all respects with Rule 16b-3 promulgated
under the Exchange Act and, if any Plan provision is later found not to be in
compliance with such Rule, the provision shall be deemed null and void, and in
all events this Plan shall be construed in favor of its meeting the
requirements of Rule 16b-3. Notwithstanding anything in this Plan to the
contrary, the Board, in its absolute discretion, may bifurcate this Plan so as
to restrict, limit or condition the use of any provision of this Plan to
participants who are officers and directors subject to Section 16(b) of the
Exchange Act without so restricting, limiting or conditioning other Plan
participants.

Subject to the provisions of this Plan, and with a view to effecting its
purpose, the Plan Administrator shall have sole authority, in its absolute
discretion, to (a) construe and interpret this Plan; (b) define the terms used
in this Plan; (c) prescribe, amend and rescind rules and regulations relating
to this Plan; (d) correct any defect, supply any omission or reconcile any
inconsistency in this Plan; (e) determine the individuals to whom Options shall
be granted under this Plan and whether the Option is an Incentive Stock Option
or a Non-Qualified Stock Option; (f) determine the time or times at which
Options shall be granted under this Plan; (g) determine the number of shares of
Common Stock subject to each Option, the exercise price of each Option, the
duration of each Option and the times at which each Option shall become
exercisable; (h) determine all other terms and conditions of Options; and (i)
make all other determinations necessary or advisable for the administration of
this Plan. All decisions, determinations and interpretations made by the Plan
Administrator shall be binding and conclusive on all participants in this Plan
and on their legal representatives, heirs and beneficiaries.

3. ELIGIBILITY.
Incentive Stock Options may be granted to any individual who, at the time the
Option is granted, is an employee of the Company or any Related Corporation (as
defined below), including employees who are directors of the Company
("Employees"). Non-Qualified Stock Options may be granted to Employees and to
such other persons as the Plan Administrator shall select. Options may be
granted in substitution for outstanding Options of another corporation in
connection with the merger, consolidation, acquisition of property or stock or
other reorganization between such other corporation and the Company or any
subsidiary of the Company. Options also may be granted in exchange for
outstanding Options. Any person to whom an Option is granted under this Plan is
referred to as an "Optionee."


     





  
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As used in this Plan, the term "Related Corporation," when referring to a
subsidiary corporation, shall mean any corporation (other than the Company) in
an unbroken chain of corporations beginning with the Company if, at the time of
the granting of the Option, each of the corporations other than the last
corporation in the unbroken chain owns stock possessing 50 percent or more of
the total combined voting power of all classes of stock of one of the other
corporations in such chain. When referring to a parent corporation, the term
"Related Corporation" shall mean any corporation (other than the Company) in an
unbroken chain of corporations ending with the Company if, at the time of
granting of the Option, each of the corporations other than the Company owns
stock possessing 50 percent or more of the total combined voting power of all
classes of stock of one of the other corporations in such chain.

4. STOCK.
The Plan Administrator is authorized to grant Options to acquire up to a total
of five hundred thousand (500,000) shares of the Company's authorized but
unissued, or reacquired, Common Stock. The number of shares with respect to
which Options may be granted hereunder is subject to adjustment as set forth in
Section 5(m) hereof. In the event that any outstanding Option expires or is
terminated for any reason, the shares of Common Stock allocable to the
unexercised portion of such Option may again be subject to an Option to the
same Optionee or to a different person eligible under Section 3 of this Plan.

5. TERMS AND CONDITIONS OF OPTIONS.
Each Option granted under this Plan shall be evidenced by a written agreement
approved by the Plan Administrator (the "Agreement"). Agreements may contain
such additional provisions, not inconsistent with this Plan, as the Plan
Administrator in its discretion may deem advisable. All Options also shall
comply with the following requirements:

     (a) Number of Shares and Type of Option. Each Agreement shall state the
number of shares of Common Stock to which it pertains and whether the Option is
intended to be an Incentive Stock Option or a Non-Qualified Stock Option. The
aggregate fair market value (determined at the Date of Grant, as defined below)
of the stock with respect to which Incentive Stock Options are exercisable for
the first time by the Optionee during any calendar year (granted under this
Plan and all other Incentive Stock Option plans of the Company, a Related
Corporation or a predecessor corporation) shall not exceed $100,000, or such
other limit as may be prescribed by the Code as it may be amended from time to
time. Any Option which exceeds the annual limit shall not be void but rather
shall be a Non-Qualified Stock Option.

     (b) Date of Grant. Each Agreement shall state the date the Plan
Administrator has deemed to be the effective date of the Option for purposes of
this Plan (the "Date of Grant").

     (c) Option Price. Each Agreement shall state the price per share of Common
Stock at which it is exercisable. The exercise price shall be fixed by the Plan
Administrator at whatever price; the Plan Administrator may determine in the
exercise of its sole discretion; provided, that the per share exercise price
for any Option granted following the effective date of registration of any of
the Company's securities under Section 12 of the Exchange Act shall not be less
than the fair market value per share of the Common Stock at the Date of Grant
as determined by the Plan Administrator in good faith; provided further, that
the per share exercise price for an Incentive Stock Option shall not be less
than the fair market value per share of the Common Stock at the Date of Grant
as determined by the Plan Administrator in good faith; provided further, that
with respect to Incentive Stock Options granted to greater-than-10 percent
shareholders of the Company (as determined under Section 424(d) of the Code),
the exercise price per share shall not be less than 110 percent of the fair
market value per share of the Common Stock at the Date of Grant; and, provided
further, that Incentive Stock Options granted in substitution for outstanding
Options of another corporation in connection with the merger, consolidation,
acquisition of property or stock or other reorganization involving such other
corporation and the Company or any subsidiary of the Company may be granted
with an exercise price equal to the exercise price for the substituted Option
of the other corporation, subject to any adjustment consistent with the terms
of the transaction pursuant to which the substitution is to occur, in
accordance with Code Section 424(a).

     (d) Duration of Options. At the time of the grant of the Option, the Plan
Administrator shall designate, subject to paragraph 5(g) below, the expiration
date of the Option, which date shall not be later than 10 years from the Date
of Grant in the case of Incentive Stock Options, provided, that the expiration
date of any Incentive Stock Option granted to a greater-than-10 percent
shareholder of the Company (as determined under Section 424(d) of the Code)
shall not be later than five years from the Date of Grant. In the absence of
action to the contrary by the Plan
<PAGE>   3
Administrator in connection with the grant of a particular Option and except in
the case of Incentive Stock Options as described above, all Options granted
under this Plan shall expire 10 years from the Date of Grant.

        (e) Vesting Schedule. No Option shall be exercisable until it has
vested. The vesting schedule for each Option shall be specified by the Plan
Administrator at the time of grant of the Option, provided, that if no vesting
schedule is specified at the time of grant, the Option shall vest according to
the following schedule

<TABLE>
<CAPTION>

                NUMBER OF YEARS                 PERCENTAGE OF TOTAL OPTION
            FOLLOWING DATE OF GRANT                    TO BE VESTED
            ------------------------            ---------------------------

           <S>                                  <C>
                        1                                  33.3%
                        2                                  66.6%
                        3                                 100.0%
</TABLE>

        (f) Acceleration of Vesting. The vesting of one or more outstanding
Options may be accelerated by the Plan Administrator at such times and in such
amounts as it shall determine in its sole discretion. The vesting of Options
also shall be accelerated under the circumstances described in Section 5(m).

        (g) Term of Option. Vested Options shall terminate, to the extent not
previously exercised, upon the occurrence of the first of the following events:
(i) the expiration of the Option, as designated by the Plan Administrator in
accordance with Section 5(d) above; (ii) the expiration of three (3) months from
the date of an Employee Optionee's termination of employment with the Company or
any Related Corporation for any reason whatsoever other than death or disability
unless, in the case of a Non-Qualified Stock Option, the exercise period is
extended by resolution adopted by the Plan Administrator until a date not
later than the expiration date of the Option; or (iii) the expiration of one
year from (A) the date of death of the Optionee or (B) cessation of an Employee
Optionee's employment by reason of Disability (as defined below). If an Employee
Optionee's employment is terminated by death, any Option held by the Optionee
shall be exercisable only by the person or persons to whom such Optionee's
rights under such Option shall pass by the Optionee's will or by the laws of
descent and distribution of the state or county of the Employee Optionee's
domicile at the time of death. Notwithstanding the foregoing, an Optionee may
during the Optionee's lifetime, designate a person who may exercise the option
after the Optionee's death by giving written notice of such designation to the
Plan Administrator. Such designation may be changed from time to time by the
Optionee by giving written notice to the Plan Administrator revoking any earlier
designation and making a new designation. "Disability" shall have the same
meaning provided in Code Section 22(e)(3). The Plan Administrator shall
determine whether an Optionee has incurred a Disability on the basis of medical
evidence acceptable to the Plan Administrator. Upon making a determination of
Disability, the Committee shall, for purposes of the Plan, determine the date of
an Optionee's termination of employment.

Unless accelerated in accordance with Section 5(f) above, unvested Options shall
terminate immediately upon termination of employment of the Optionee by the
Company for any reason whatsoever, including death or disability. If, in the
case of an Incentive Stock Option, an Optionee's relationship with the Company
changes (e.g. from an Employee to a non-Employee, such as a consultant) such
change shall constitute a termination of an Optionee's employment with the
Company and the Optionee's Incentive Stock Option shall terminate in accordance
with this subsection. For purposes of this Plan, transfer of employment between
or among the Company and/or any Related Corporation shall not be deemed to
constitute a termination of employment with the Company or any Related
Corporations. For purposes of this subsection with respect to Incentive Stock
Options, employment shall be deemed to continue while the Optionee is on
military leave, sick leave or other bonafide leave of absence (as determined by
the Plan Administrator). The foregoing notwithstanding, employment shall not be
deemed to continue beyond the first 90 days of such leave, unless the Optionee's
re-employment rights are guaranteed by statute or by contract.

        (h) Exercise of Options. Options shall be exercisable, either all or in
part, at any time after vesting until termination. If less than all of the
shares included in the vested portion of any Option are purchased, the
remainder may be purchased at any subsequent time prior to the expiration of
the Option term. No portion of any Option for less than 50 shares (as adjusted
pursuant to Section 5(m) below) may be exercised, provided that if the vested
portion of any Option is less than 50 shares, it may be exercised with respect
to all shares for which it is vested. Only whole shares may be issued pursuant
to an Option, and to the extent that an Option covers less than one share, it
is unexercisable. Options or portions thereof may be exercised by giving written
notice to the Company, which notice shall specify the number of shares to be
purchased and be accompanied by either (i) payment in the amount of the
aggregate exercise price for the Common Stock so purchased, which payment shall
be in the form specified in Section 5(i) below, or (ii)
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upon prior consent of the Plan Administrator, delivery of an irrevocable
subscription agreement obligating the Optionee to take and pay for the shares
of Common Stock to be purchased within one year of the date of such exercise.
The Company shall not be obligated to issue, transfer or deliver a certificate
of Common Stock to any Optionee, or to his personal representative, until the
aggregate exercise price has been paid for all shares for which the Option
shall have been exercised and adequate provision has been made by the Optionee
for satisfaction of any tax withholding obligations associated with such
exercise. During the lifetime of an Optionee, Options are exercisable only by
the Optionee.

     (i)  Payment upon Exercise of Option. Upon the exercise of any Option, the
aggregate exercise price shall be paid to the Company in cash or by certified
or cashier's check. In addition, upon approval of the Plan Administrator, an
Optionee may pay for all or any portion of the aggregate exercise price by
delivering to the Company shares of Common Stock previously held by such
Optionee or, upon the Optionee's request and the consent of the Plan
Administrator, by having shares withheld from the amount of shares of Common
Stock to be received by the Optionee, provided the Plan Administrator shall have
complete discretion whether to honor or deny the Optionee's request. The shares
of Common Stock received or withheld by the Company as payment for shares of
Common Stock purchased upon the exercise of Options shall have a fair market
value at the date of exercise (as determined by the Plan Administrator) equal
to the aggregate exercise price (or portion thereof) to be paid by the Optionee
upon such exercise.

     (j)  Rights as a Shareholder. An Optionee shall have no rights as a
shareholder with respect to any shares covered by an Option until such Optionee
becomes a record holder of such shares, irrespective of whether such Optionee
has given notice of exercise. Subject to the provisions of Section 5(m) hereof,
no rights shall accrue to an Optionee and no adjustments shall be made on
account of dividends (ordinary or extraordinary, whether in cash, securities or
other property) or distributions or other rights declared on, or created in,
the Common Stock for which the record date is prior to the date the Optionee
becomes a record holder of the shares of Common Stock covered by the Option,
irrespective of whether such Optionee has given notice of exercise.

     (k)  Transfer of Option. Options granted under this Plan and the rights
and privileges conferred by this Plan may not be transferred, assigned, pledged
or hypothecated in any manner (whether by operation of law or otherwise) other
than by will or by applicable laws of descent and distribution, and shall not
be subject to execution, attachment or similar process. Upon any attempt to
transfer, assign, pledge, hypothecate or otherwise dispose of any Option or of
any right or privilege conferred by this Plan contrary to the provisions
hereof, or upon the sale, levy or any attachment or similar process upon the
rights and privileges conferred by this Plan, such Option shall thereupon
terminate and become null and void. The foregoing notwithstanding, with respect
to a Non-Qualified Stock Option, an Optionee may transfer the Option to a
revocable trust created by the Optionee for the benefit of his or her
descendants, to an immediate family member or to a partnership in which only
immediate family members or such trusts are partners.

     (l)  Securities Regulation and Tax Withholding

     (1)  Shares shall not be issued with respect to an Option unless the
     exercise of such Option and the issuance and delivery of such shares shall
     comply with all relevant provisions of law, including, without limitation,
     any applicable state securities laws, the Securities Act of 1933, as
     amended, the Exchange Act, the rules and regulations thereunder and the
     requirements of any stock exchange upon which such shares may then be
     listed, and such issuance shall be further subject to the approval of
     counsel for the Company with respect to such compliance, including the
     availability of an exemption from registration for the issuance and sale of
     such shares. The inability of the Company to obtain from any regulatory
     body the authority deemed by the Company to be necessary for the lawful
     issuance and sale of any shares under this Plan, or the unavailability of
     an exemption from registration for the issuance and sale of any shares
     under this Plan, shall relieve the Company of any liability with respect to
     the non-issuance or sale of such shares.

     As a condition to the exercise of an Option, the Company may require the
     Optionee to represent and warrant in writing at the time of such exercise
     that the shares are being purchased only for investment and without any
     then-present intention to sell or distribute such shares. At the option of
     the Company, a stop-transfer order against such shares may be placed on
     the stock books and records of the Company, and a legend indicating that
     the stock may not be pledged, sold or otherwise transferred unless an
     opinion of counsel is provided.
<PAGE>   5
stating that such transfer is not in violation of any applicable law or
regulation, may be stamped on the certificates representing such shares in order
to assure an exemption from registration. The Plan Administrator may also
require such other documentation as may from time to time be necessary to comply
with federal and state securities laws. THE COMPANY HAS NO OBLIGATION TO
UNDERTAKE REGISTRATION OF OPTIONS OR THE SHARES OF STOCK ISSUABLE UPON THE
EXERCISE OF OPTIONS.

     (2) As a condition to the exercise of any Option granted under this Plan,
the Optionee shall make such arrangements as the Plan Administrator may require
for the satisfaction of any federal, state or local withholding tax obligations
that may arise in connection with such exercise.

     (3) The issuance, transfer or delivery of certificates of Common Stock
pursuant to the exercise of Options may be delayed, at the discretion of the
Plan Administrator, until the Plan Administrator is satisfied that the
applicable requirements of the federal and state securities laws and the
withholding provisions of the Code have been met.

(m) Stock Dividend, Reorganization or Liquidation.

     (1) If (i) the Company shall at any time be involved in a transaction
described in Section 424(a) of the Code (or any successor provision) or any
"corporate transaction" described in the regulations thereunder; (ii) the
Company shall declare a dividend payable in, or shall subdivide or combine, its
Common Stock; or (iii) any other event with substantially the same effect shall
occur, the Plan Administrator shall, with respect to each outstanding Option,
proportionately adjust the number of shares of Common Stock and/or the exercise
price per share so as to preserve the rights of the Optionee substantially
proportionate to the rights of the Optionee prior to such event, and to the
extent that such action shall include an increase or decrease in the number of
shares of Common Stock subject to outstanding Options, the number of shares
available under Section 4 of this Plan shall automatically be increased or
decreased, as the case may be, proportionately, without further action on the
part of the Plan Administrator, the Company or the Company's shareholders. The
foregoing adjustments in the shares subject to Options shall be made by the Plan
Administrator, or by any successor administrator of this Plan, or by the
applicable terms of any assumption or substitution document.

     (2) If the Company is liquidated or dissolved, Options must be exercised
prior to the effective date of such liquidation or dissolution. If the Option
holders do not exercise their Options prior to such effective date, each
outstanding Option shall terminate as of the effective date of the liquidation
or dissolution.

     (3) The grant of an Option shall not affect in any way the right or power
of the Company to make adjustments, reclassifications, reorganizations or
changes of its capital or business structure, to merge, consolidate or dissolve,
to liquidate or to sell or transfer all or any part of its business or assets.

6. EFFECTIVE DATE; TERM.
This Plan shall be effective as of April 1, 1997. Options may be granted by the
Plan Administrator from time to time thereafter until April 1, 2007. Termination
of this Plan shall not terminate any Option granted prior to such termination.
Any Incentive Stock Options granted by the Plan Administrator prior to the
approval of this Plan by a majority of the shareholders of the Company shall be
granted subject to ratification of this Plan by the shareholders of the Company,
and if shareholder ratification is not obtained, each and every Incentive Stock
Option shall become a Non-Qualified Stock Option.

7. NO OBLIGATIONS TO EXERCISE OPTION.
The grant of an Option shall impose no obligation upon the Optionee to exercise
such Option.

8. NO RIGHT TO OPTIONS OR TO EMPLOYMENT.
Whether or not any Options are to be granted under this Plan shall be
exclusively within the discretion of the Plan Administrator, and nothing
contained in this Plan shall be construed as giving any person any right to
participate under this Plan. The grant of an Option shall in no way constitute
any form of agreement or understanding binding on the Company or any Related
Corporation, express or implied, that the Company or any Related Corporation
will employ or contract with an Optionee for any length of time.





          
<PAGE>   6

9. APPLICATION OF FUNDS.
The proceeds received by the Company from the sale of Common Stock issued upon
the exercise of Options shall be used for general corporate purposes, unless
otherwise directed by the Board.

10. INDEMNIFICATION OF PLAN ADMINISTRATOR.              
In addition to all other rights of indemnification they may have as members 
of the Board, members of the Plan Administrator shall be indemnified by
the Company for all reasonable expenses and liabilities of any type or nature,
including attorneys' fees, incurred in connection with any action, suit or
proceeding to which they or any of them are a party by reason of, or in
connection with, this Plan or any Option granted under this Plan, and against
all amounts paid by them in settlement thereof (provided that such settlement
is approved by independent legal counsel selected by the Company), except to
the extent that such expenses relate to matters for which it is adjudged that
such Plan Administrator member is liable for willful misconduct, provided, that
within 15 days after the institution of any such, action, suit or proceeding,
the Plan Administrator member involved therein shall, in writing, notify the
Company of such action, suit or proceeding, so that the Company may have the
opportunity to make appropriate arrangements to prosecute or defend the same.

11. AMENDMENT OF PLAN. 
The Plan Administrator may, at any time modify, amend or terminate this
Plan and Options granted under this Plan, provided, that no amendment with
respect to an outstanding Option shall be made over the objection of the
Optionee thereof; and provided further, that the approval of the holders of a
majority of the Company's outstanding shares of voting capital stock is
required within 12 months before or after the adoption by the Plan
Administrator of any amendment that (i) will permit the granting of Options to
a class of persons other than those currently eligible to receive Options under
this Plan; (ii) will increase the number of shares available pursuant to
Options issued under this Plan; or (iii) require shareholder approval under
applicable law, including Section 16(b) of the Exchange Act. Without limiting
the generality of the foregoing, the Plan Administrator may modify grants to
persons who are eligible to receive Options under this Plan who are foreign
nationals or employed outside the United States to recognize differences in
local law, tax policy or custom.

Date Approved by Board of Directors of Company March 31, 1997  
<PAGE>   7
Exhibit A


Notice of Election to Exercise

This Notice of Election to Exercise shall constitute proper notice pursuant to
Section 5(h) of the Software Testing Laboratories, Inc. 1995 Stock Option Plan
(the "Plan") and Section 7 of that certain Non-qualified Stock Option Agreement
(the "Agreement") dated as of __________________ between Software Testing
Laboratories, Inc. (the "Company") and the undersigned.

The undersigned hereby elects to exercise Optionee's option to purchase _______
shares of the common stock of the Company at a purchase price of $_________ per
share, for aggregate consideration of $_______, on the terms and conditions set
forth in the Agreement and the Plan. Such aggregate consideration, in the form
specified in Section 7 of the Agreement, accompanies this Notice.

The undersigned has executed this Notice this __ day of ______________, _____.


                              OPTIONEE



                              ______________________________
                              Name (type or print)


                              ______________________________
                              Signature










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