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                                                                   Exhibit 4.5

                             TERRAGEN DISCOVERY INC.

                           EMPLOYEE STOCK OPTION PLAN

         The Board of Directors of TerraGen Discovery Inc. (the "Company") has
adopted this Stock Option Plan together with Schedule "A" hereto, pursuant to
which certain directors, officers and employees of the Company and its
subsidiaries whose efforts will dictate, to a large extent, the future growth
and success of the Company and its subsidiaries on a consolidated basis, may be
granted options to purchase Common Shares of its capital and thereby share in
its future growth and success.

                                    ARTICLE 1
                                 INTERPRETATION

         In this Plan, unless there is something in the subject matter or
context inconsistent therewith:

         (a)  "Average Market Price" means the average closing price of the
              common shares on The Toronto Stock Exchange or, if the Common
              Shares are not listed on such Exchange, on such other exchange or
              exchanges on which the Common Shares are listed during a period of
              five consecutive trading days before a specified date; for such
              purposes, the average closing price shall be determined by
              dividing the aggregate closing prices of the common shares on The
              Toronto Stock Exchange or if the Common Shares are not listed on
              such Exchange, on such other exchange or exchanges on which the
              Common Shares are listed, during such five consecutive trading
              days by five,

         (b)  "Board of Directors" means the board of directors of the Company,

         (c)  "Common Shares" mean the common shares without par value in the
              capital of the Company as constituted on the effective date of the
              Plan, provided that if the exercise rights of an Optionee are
              subsequently adjusted pursuant to Article 19 hereof, "Common
              Shares" will thereafter mean the shares or other securities or
              property which an Optionee is entitled to purchase after giving
              effect to such adjustment,

         (d)  "Company" means TerraGen Discovery Inc.,

         (e)  "Eligible Person" means a director, officer or employee of the
              Company or director, officer or employee of a Subsidiary named by
              the Board of Directors as set forth in, and who otherwise meets
              the qualifications of Article 6 hereof, but specifically excludes
              any person deemed ineligible by operation of the Securities Laws.

         (f)  "Exchange" means The Toronto Stock Exchange or, if the Common
              Shares are not listed on such Exchange, on such other exchange or
              exchanges on which the Common Shares are listed.

         (g)  "Fair Market Value" means, with respect to a Common Share subject
              to Option, the closing price of the Common Shares on the Exchange
              on the day immediately preceding the day of grant. If no Common
              Shares have been traded on such day, the Fair Market Value shall
              be established on the same basis on the last previous day for
              which a trade was reported by such Exchange. If the Common Shares
              are not listed and posted for trading on such Exchange on such
              day, the Fair Market Value shall be such price per Common Share as
              the Board of Directors, acting in good faith, may determine,

         (h)  "Insider" means an insider as defined under Securities Laws,

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         (i)  "Option" means an option for the purchase of Common Shares as
              described herein and granted to an Eligible Person pursuant to the
              terms and conditions hereof and as evidenced by an Option
              Agreement,

         (j)  "Option Agreement" means an agreement evidencing an Option,
              entered into by and between the Company and an Eligible Person,

         (k)  "Option Exercise Price" means the price per Common Share at which
              an Optionee may purchase Common Shares pursuant to an Option,
              provided that if such price is adjusted pursuant to Article 19
              hereof, "Option Exercise Price" will thereafter mean the price per
              Common Share at which an Optionee may purchase Common Shares
              pursuant to an Option after giving effect to such adjustment,

         (l)  "Optionee" means an Eligible Person who holds an Option under the
              Plan,

         (m)  "Plan" means this Stock Option Plan and, as it relates only to
              residents of the United Kingdom this Plan as modified by the terms
              of Schedule "A" hereto, as may be amended or modified from time to
              time pursuant to and in accordance with the provisions hereof,

         (n)  "Schedule "A" means the modifications to the Plan relating only to
              those Eligible Persons resident in the United Kingdom as set forth
              in the attached Schedule "A",

         (o)  "Securities Laws" means, unless otherwise specified, the
              applicable securities laws and regulations of Canada, the United
              States or of the United Kingdom, or any political subdivision of
              either, and the by-laws, rules and regulations of any stock
              exchange or other trading facility upon which the Common Shares
              are listed or traded, as the case may be,

         (p)  "Subsidiary" means any corporation in which more than 50% of the
              outstanding shares carrying the right to vote at all times
              (provided the ownership of such shares confers the right to elect
              at least a majority of the board of directors of such corporation)
              are for the time being owned by or held for, directly or
              indirectly, the Company,

         (q)  "United Kingdom" means the United Kingdom of Great Britain and
              Northern Ireland, its territories, possessions and other areas
              subject to its jurisdiction, and

         (r)  "United States" means the United States of America (including the
              States and the District of Columbia), its territories, its
              possessions and other areas subject to its jurisdiction.

                                    ARTICLE 2
                               PURPOSE OF THE PLAN

         The  purpose of this Plan is to promote the interest of the Company by:

         (a)  attracting and retaining persons of outstanding competence whose
              efforts will dictate, to a large extent, the future growth and
              success of the Company,

         (b)  furnishing Eligible Persons with greater incentive to develop and
              promote the growth and success of the Company, and

         (c)  furthering the identity of interests of Eligible Persons with
              those of the shareholders of the Company generally by encouraging
              Eligible Persons to acquire share ownership in the Company.


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         The Company believes that these purposes may best be effected by
granting to Eligible Persons from time to time options to purchase Common
Shares.

                                    ARTICLE 3
                      EFFECTIVE DATE AND TERMS OF THE PLAN

         The effective date of this Plan shall be May 15, 1999 the date of its
adoption by the Board of Directors subject to all necessary regulatory
approvals.

         The terms of the Plan as set forth excluding Schedule "A" shall govern
the granting of Options to Eligible Persons excluding those who are residents of
the United Kingdom. The Plan as modified by the terms of Schedule "A" shall
govern the granting of Options to those Eligible Persons who are residents of
the United Kingdom. As it applies to those Eligible persons who are residents of
the United Kingdom, where the terms of the Plan and the terms of Schedule "A"
are inconsistent the Plan as modified by the terms of Schedule "A" shall govern.

                                    ARTICLE 4
                        COMMON SHARES SUBJECT TO THE PLAN

         The maximum number of Common Shares which may be subject to all Options
from time to time granted pursuant to this Plan shall not exceed two million. If
any Option expires or terminates under this Plan for any reason without being
exercised in full, the Common Shares covered by such Option, or the unexercised
portion of such Option, as the case may be, shall be returned to the Plan and
again become subject to Options which may be granted pursuant to this Plan.

         In the event that the Company applies to list its shares on an Exchange
and as a consequence the total number of shares available under the Plan is
caused to be adjusted, the number of outstanding Options previously granted to
the Optionees shall in turn be adjusted in accordance with the terms of Article
19.

                                    ARTICLE 5
                           ADMINISTRATION OF THE PLAN

         This Plan shall be administered by the Board of Directors. The Board of
Directors is authorized, subject to the provisions of this Plan, to establish
from time to time such rules and regulations as are, in the opinion of the Board
of Directors, appropriate for the proper administration of this Plan, and to
make such determinations and to take such steps in connection with this Plan as
are permitted pursuant to this Plan and as in the o'inion of the Directors are
necessary or desirable to further the purposes of this Plan. The Directors
shall, subject to the provisions of this Plan, name eligible Persons, determine
the time or times when Options shall be granted, determine the number of Common
Shares for which any Option may be granted to an Eligible Person and determine
the Option Exercise Price at which Common Shares may be purchased under any
Option to be granted to an Eligible Person.

         Any question arising as to interpretation of this Plan, any Option or
any Option Agreement shall be determined by the Board of Directors and such
determination shall be final, conclusive and binding on all parties. When used
herein, the term "Board of Directors" shall be deemed to include a committee of
directors acting on behalf of the Board of Directors.

                                    ARTICLE 6
                                   ELIGIBILITY

         The Board of Directors may, subject to the provisions of this Plan,
name from time to time as an Eligible Person any director, officer or employee
of the Company or any director, officer or employee of any Subsidiary who is or
will be, in the opinion of the Board of Directors, one of the directors,
officers or employees of the Company or of a Subsidiary responsible for the
management, growth and success of the Company and whose participation in this
Plan will, in the opinion of the Board of Directors, accomplish the purpose of
this Plan. The Board of Directors may establish, from time to time, guidelines
by which it names



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Eligible Persons and amend, from time to time, any such guidelines so
established. Such guidelines may (but need not) include the following: the
directors, officers or employees whose efforts will dictate, to a large extent,
the future growth and success of the Company, the need to attract an exceptional
person as a director, officer or employee or to recognize a key assignment in
the management of assets that are significant or crucial to the Company's
strategic plan.

                                    ARTICLE 7
                                GRANT OF OPTIONS

         Options pursuant to the terms of this Plan may be granted from time to
time by the Company acting through the Board of Directors. The date on which an
Option shall be deemed to have been granted under this Plan shall be the date
the Board of Directors authorizes the grant of such Option or such later date as
may be determined by the Board of Directors at the time that the grant of such
Option is authorized.

         Each Option granted pursuant to this Plan shall be evidenced by an
Option Agreement executed on behalf of the Company by any director of the Board
of Directors and each Option Agreement shall incorporate such terms and
conditions as the Board of Directors in its discretion deems consistent with the
terms of this Plan. The Board of Directors may, with the written consent of the
Optionee, amend an Option Agreement to the extent that the Board of Directors
acting in its discretion deems consistent with the terms of this Plan.

                                    ARTICLE 8
                             NUMBER OF COMMON SHARES

         The number of Common Shares for which any Option may be granted shall
be determined by the Board of Directors, but shall not be greater than the
maximum number or value of Common Shares which may be acquired by an Optionee
upon the exercise of such Option pursuant to the Securities Laws applicable to
them. The Board of Directors may establish, from time to time, guidelines by
which it determines the number of Common Shares for which any Option may be
granted and amend, from time to time, any such guidelines. Such guidelines may
be based upon the Eligible Person's base salary or other factors considered
relevant to the Board of Directors. The number of Common Shares to be purchased
upon the exercise of any Option shall be subject to adjustment pursuant to
Article 19 hereof.

                                    ARTICLE 9
                              OPTION EXERCISE PRICE

         The Option Exercise Price under each Option granted pursuant to this
Plan to an Eligible Person shall be determined by the Board of Directors but
shall not be less than the greater of the Fair Market Price on the day of grant
or the nominal value of the Company's Common Shares, if any. The Option Exercise
Price determined for any Option shall be subject to adjustment pursuant to
Article 19 hereof.

                                   ARTICLE 10
                                TERMS OF OPTIONS

         Each option granted to an Eligible Person pursuant to this Plan shall,
subject to the provisions of Article 17 hereof, be exercisable in whole or in
part at any time after the date on which the Option was granted and shall,
subject to early termination in accordance with Article 11 hereof, expire
automatically on the earlier of

         (a)  the date on which the Option is exercised in respect of all Common
              Shares that may be acquired thereunder, and

         (b)  the date which is the earlier of the expiry date as determined by
              the Board of Directors or the 10th anniversary of the date on
              which the Option was granted, except that:


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              (i)  in the case of the death of an Optionee, all or any of the
                   Common Shares covered by the Option may be purchased by the
                   legal representative of such Optionee, or by the person or
                   persons to whom his rights under the Option Agreement shall
                   pass by will or the laws of devolution or distribution and
                   descent, prior to the earlier of

                   (A)   the date which is one year from the date of the death
                         of such Optionee, and

                   (B)   the date which is the earlier of the expiry date as
                         determined  by the Board of Directors or the l0th
                         anniversary of the date on which the Option was
                         granted, and

              (ii) in the case where an Optionee ceases, for any reasons other
                   than death, to be a director, officer or employee of the
                   Company or a director, officer or employee of a Subsidiary
                   after the date on which the Option was granted to such
                   Optionee, all or any of the Common Shares covered by the
                   Option may be purchased by such Optionee prior to the earlier
                   of

                   (A)   the date which is 30 days from the date such Optionee
                         so ceases to be a director, officer or employee of the
                         Company or a director, officer or employee of any
                         Subsidiary, and

                   (B)   the date which is the earlier of the expiry date as
                         determined by the Board of Directors or the l0th
                         anniversary of the date on which the Option was grant.


                                   ARTICLE 11
                             TERMINATION OF OPTIONS

         Each Option granted to an Eligible Person pursuant to this Plan shall
terminate 30 days following the date the Optionee ceases for any reason to be a
director, officer or employee of the Company, or a director, officer or employee
of a Subsidiary, except as provided in subparagraph (i) of Article 10 and in
Article 13 hereof. Not withstanding the forgoing in the event of termination of
the Optionee for cause each Option granted to such Optionee shall terminate
immediately.

         A change in the duties or position of an Optionee or the transfer of
such Optionee from a position with the Company to a position with a Subsidiary,
or vice versa, shall not trigger the termination of such Optionee's Option
provided such Optionee remains a director, officer or employee of the Company or
a director, officer or employee of any Subsidiary.

                                   ARTICLE 12
                          NONTRANSFERABILITY OF OPTIONS

         Any Option granted pursuant to this Plan may not be transferred or
assigned except by will or the laws of devolution or distribution and descent
and, except as set forth in subparagraph (i) of Article 10 hereof, may be
exercised only by an Optionee during his lifetime. The restriction on transfer
described in this Article 12 shall be incorporated into each Option Agreement.

                                   ARTICLE 13
                               EXERCISE OF OPTION

         Subject to the terms and conditions of this Plan, an Option may be
exercised by written notice signed by the Optionee and dated the date of
exercise, and not post-dated, stating that the Optionee elects to exercise his
rights to purchase Common Shares under such Option and the number of Common
Shares in respect of which such Option is being exercised, accompanied by full
payment for the Commons Shares being purchased under such Option delivered to
the Company at its principal office at Suite 300 - 2386 East Mall (UBC),
Vancouver, B.C. V6T ID (or such other address of the principal office of the
Company at the time of exercise) addressed to the attention of


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the Secretary of the Company. Delivery of any notice of exercise accompanied by
payment may be made by personal delivery, by courier service or by agent.

         Upon exercise of an Option, a certificate or certificates evidencing
the Common Shares in respect of which the Option is exercised shall be delivered
to the Optionee.

         Notwithstanding the time or times specifically provided herein or in an
option Agreement for the vesting or exercise of an Option, the Optionee may
elect to purchase all or any of the Common Shares remaining subject to such
Option at any time if a "take-over bid" or an "issuer bid" (within the meaning
of any Securities Laws or other federal, provincial or state laws or
regulations) is made for or by the Company, respectively.

                                   ARTICLE 14
                                     PAYMENT

         Payment of the Option Exercise Price for Common Shares purchased under
an Option must be made in full in lawful money of Canada or by certified cheque
payable at par at the time the notice of exercise is delivered to the Company.

                                   ARTICLE 15
                            SHARE APPRECIATION RIGHT

         An Optionee may, if determined by the Board of Directors, have the
right (the "Right"), when entitled to exercise an option, to terminate such
Option in whole or in part by notice in writing to the Company and, in lieu of
receiving Common Shares pursuant to the exercise of the Option, shall receive
instead and at no cost to the Optionee that number of Common Shares,
disregarding fractions, which, when multiplied by the Average Market Price
immediately prior to the exercise of the Right, have a total value equal to the
product of the number of Common Shares subject to Option times the difference
between the Average Market Price immediately prior to the exercise of the Right
and the Option Exercise Price. No such share appreciation rights will exist,
however, until the Board of Directors formally approves the activation of this
Right.

                                   ARTICLE 16
                          REPRESENTATIONS BY OPTIONEES

         Each Option Agreement shall provide that upon each exercise of an
Option, the Optionee (including for the purposes of this Article 16 each other
person who, pursuant to subparagraph (i) of Article 10 hereof, may purchase
Common Shares under an Option granted to an Eligible Person) shall, if so
requested by the Company, represent and agree in writing that:

         (a)  the person is, or the Optionee was, a director, officer or
              employee of the Company or a director, officer or employee of any
              Subsidiary and has not been induced to purchase the Common Shares
              by expectation of employment or continued employment,

         (b)  the person is purchasing the Common Shares purchased pursuant to
              the exercise of such Option as principal for the Optionee's own
              account (or if such Optionee is deceased, for the account of the
              estate of such deceased Optionee) for investment purposes, and not
              with a view to the distribution or resale thereof to the public,

         (c)  the person will, prior to and upon any sale or disposition of any
              of the Common Shares purchased pursuant to the exercise of such
              Option, comply with the Securities Laws and any other federal,
              provincial or state laws or regulations and the company's articles
              to the extent that such laws, regulations or articles are
              applicable to such sale or disposition, and


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         (d)  such Optionee (or such other person) will not offer, sell or
              deliver any of the Common Shares purchased pursuant to the
              exercise of such Option, directly or indirectly, in the United
              States or to any citizen or resident of, or any corporation,
              partnership or other entity created or organized in or under the
              laws of, the United States, or any estate or trust the income of
              which is subject to United States federal income taxation
              regardless of its source, except in compliance with United States
              federal and state securities laws. The Optionee acknowledges that
              the Company has the right to place any restriction or legend on
              any securities issued pursuant to the Option Agreement or this
              Plan including, but in no way limited to, placing a legend to the
              effect that the securities have not been registered under the
              Securities Act (1933) of the United States and may not be offered
              or sold in the United States unless registration or an exemption
              from registration is available.

         The Company may employ other procedures and require further
documentation from an Optionee to ensure compliance with all applicable laws.

         The issue and sale of Common Shares pursuant to any Option granted
under this Plan is specially conditioned on such issue and sale being made in
compliance with the Securities Laws, and the Company shall have no obligation to
issue or sell any Common Shares pursuant to the exercise of any Option unless
the Board of Directors determines in its sole discretion that such issue and
sale will be made in compliance with the Securities Laws. The Company will be
entitled to take such action as it deems necessary to restrict the
transferability in the United States of any Common Shares acquired on exercise
of any Option.

                                   ARTICLE 17
                       NOTICE TO COMMISSIONS AND EXCHANGES

         The Company will give notice to all applicable securities commissions
and other regulatory bodies in Canada, the United States and the United Kingdom
and all applicable stock exchanges and other trading facilities upon which the
Common Shares are listed or traded, as may be required, of its adoption of this
Plan and of its entering into Option Agreements with Eligible Persons and the
terms and conditions for the purchase of Common Shares under such Option
Agreements, and will use all reasonable efforts to obtain any requisite
approvals as may be required from such bodies, exchanges and trading facilities.
If such requisite approvals are not obtained, then the obligation of the Company
to issue Common Shares pursuant to the exercise of such Option shall be
terminated and the Option Exercise Price paid to the Company shall be returned
to the Optionee.

                                   ARTICLE 18
                      SUSPENSION. AMENDMENT OR TERMINATION

         This Plan shall continue until such date as the Board of Directors may
determine. The Board of Directors shall have the right at any time to suspend,
amend or terminate this Plan, subject to approval of the Exchange or other
regulatory authority governing the issuance of securities of the Company, in any
manner, including without limitation, to reflect any requirements of relevant
regulatory bodies or stock exchanges, and on behalf of the Company to enter into
amendments to any Option Agreements, but shall not have the right to:

         (a)  affect in a manner that is adverse or prejudicial to, or that
              impairs, the benefits and rights of any Optionee under any Option
              previously granted under this Plan except for the purpose of
              complying with the Securities Laws,

         (b)  decrease the number of Common Shares which may be issued pursuant
              to any Option granted under this Plan (subject to any necessary
              adjustment pursuant to Article 19 hereof),

         (c)  increase the Option Exercise Price at which Common Shares may be
              purchased pursuant to any Option granted under this Plan (subject
              to any necessary adjustment pursuant to Article 19 hereof),

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         (d)  extend the term of any Option beyond a period of 10 years, or

         (e)  grant any Option if this Plan is suspended or has been terminated.

         The full powers of the Board of Directors as provided for in this Plan
shall survive the termination of this Plan until all Options have been exercised
in full or have otherwise expired.

                                   ARTICLE 19
                                   ADJUSTMENT

         If the number of outstanding Common Shares of the Company or the number
of Common Shares available under this Plan are increased or decreased., or are
changed into or are exchanged for a different number or kind of shares or
securities or other forms of consideration, as a result of one or more
recapitalizations, restructurings, reclassifications, subdivisions,
consolidations, stock dividend, or the like, or as a consequence of listing on
the Exchange, the Board of Directors shall determine, subject to the
requirements of the Securities Laws and approval of the Exchange or other
applicable regulatory authority, the appropriate adjustments to be made in the
Option Exercise Price and/or the number and/or kind of shares or securities or
other forms of consideration which may thereafter be purchased or issued under
this Plan and for which Options may thereafter be granted and for which
outstanding Options previously granted under this Plan may thereafter be
exercised.

                                   ARTICLE 20
                                    REFERENCE

         This Plan may be referred to as the Employee Stock Option Plan of
TerraGen Discovery Inc.


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                                   SCHEDULE A

                 THE UNITED KINGDOM EMPLOYEE SHARE OPTION SCHEME

                           OF TERRAGEN DISCOVERY INC.

The terms of this Schedule A are incorporated by way of addition or substitution
with the terms of the Plan as necessary to provide Eligible Persons who are
residents of the United Kingdom rights and benefits under the Plan in accordance
with the laws of the United Kingdom.

This Schedule A incorporating the provisions of the TerraGen Discovery Inc
Employee Stock Option Plan (the "Plan") as amended by this Schedule A shall
constitute The United Kingdom Employee Share Option Scheme (the "Scheme") of
TerraGen Discovery Inc (the "Company").

1.       Subject to the succeeding paragraphs of this schedule, the terms and
         conditions of the Plan are incorporated herein except to the extent
         that they are amended as set out below. In the event of any conflict
         with the drafting of the Plan, the terms of Schedule A shall prevail
         for the purposes of the Scheme.

2.       The following definitions will apply to the Scheme:-

2.1      The expression "New Stock Option" means a Stock Option over shares in
         the Acquiring Company (as defined in Rule 10.1), or a company that has
         control of the Acquiring Company or a company which either is, or has
         control of, a company which is a member of a consortium owning either
         the Acquiring Company or a company having control of the Acquiring
         Company, granted in consideration of the release of a subsisting Stock
         Option.

2.2      "Option Agreement" shall mean the documents in the form set out in
         Appendix I to this Schedule A or in such other form as determined by
         the Board of Directors from time to time.

3.       No Stock Option shall be granted under the Scheme until the Scheme has
         been adopted by the Board of Directors.

4.       Notwithstanding Article 10(a) and (b) and Article 12 of the Plan a
         Stock Option may not be exercised or transferred by will. On the death
         of the option holder any subsisting Stock Option may only be exercised
         by his personal representatives during the period provided for in
         Article 10.

5.       The Company shall keep available sufficient un-issued Shares to satisfy
         the exercise in full of all Stock Options granted under the Scheme and
         for the time being remaining capable of being exercised.

6.       For the purposes of this Scheme, if payment is permitted in pounds
         sterling, the sterling equivalent of any amount payable on the exercise
         of a Stock Option shall be the total amount due in Canadian dollars
         converted into pounds sterling at the last published crossrate in the
         Financial Times prior to the date of exercise of such Stock Option.

7.       Any conditions imposed by the Board of Directors under Article 5 and
         Article 8 which relate to the terms of Stock Options granted under the
         Scheme shall be objective and decided at the time of grant. Subject to
         Article 13 and unless the Board of Directors so specify at the date of
         grant, a Stock Option shall not be exerciseable unless such conditions
         have been satisfied at the date of exercise and Article 10 and 11 shall
         be modified accordingly. In addition, the following words shall be read
         after references to 90 days in Article 10 and 11 "(or such other period
         as is notified to Optionees at the date of grant by the Board of
         Directors)".

8.       Article 15 shall not apply.


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9.       Article 19 of the Plan shall apply to the Scheme with the omission of
         the following words and phrases:- "stock dividend" and "and/or kind".

10.1     Article 13 shall apply with the following modifications : The Company
         shall not be obliged to issue Common Shares to Optionees unless the
         Board of Directors is satisfied that suitable arrangements have been
         made with the Optionee to satisfy any liability of the Agent pursuant
         to Rule 12 below. If a take-over bid or a issuer bid is made as
         outlined in Article 13 it is satisfied that then the Board of Directors
         shall notify all Optionees as soon as is practicable of the offer and
         the Stock Options will be exercisable during the period notified by the
         Board of Directors, conditional on the person making the offer
         ("Acquiring Company") acquiring the Company. If an Acquiring Company
         agrees to grant a New Stock Option on the release of any subsisting
         Stock Option the Optionee holds, the Optionee may instead of exercising
         his Stock Options accept the New Stock Option. A New Stock Option
         issued in consideration of the release of a Stock Option shall (subject
         to the Board of Directors determining otherwise at that time)be subject
         to the same terms as the subsisting Stock Option, including the
         conditions imposed at the time of grant of that subsisting Stock Option
         and shall import the relevant provisions of the Scheme. A New Stock
         Option shall not be exerciseable by virtue of the event pursuant to
         which it was granted.

10.2     If the Acquiring Company does not agree to grant a New Stock Option in
         exchange for the release of any subsisting Stock Option then the
         Optionee may exercise any subsisting Stock Options that have become
         exercisable from the date of the receipt of the notification from the
         Board of Directors (Rule 10.1) up to the expiry of a period specified
         in the notice, and if not so exercised it shall lapse at the expiry of
         that period.

10.3     For the purpose of this Rule 10 a person shall be deemed to have
         acquired or obtained control of a Company if he and others acting in
         concert with him have together obtained control of it.

11.      The rights and obligations of any individual under the terms of his
         office or employment with the Company and its subsidiaries shall not be
         affected by his participation in the Scheme or any right which he may
         have to participate therein and an individual who participates in the
         Scheme shall waive any and all rights to compensation or damages in
         consequence of the termination of his office or employment for any
         reason whatsoever insofar as those rights arise or may arise from his
         ceasing to have rights under or be entitled to exercise any Stock
         Option under the Scheme as a result of such termination. Neither the
         grant of a Stock Option nor any benefit which may accrue to an Optionee
         on the exercise of a Stock Option shall form part of that persons
         pensionable remuneration for the purposes of any pension scheme or
         similar arrangement which may be offered by the Company or its
         subsidiaries.

12.1     If the Optionee is liable to tax, duties or other amounts on the
         exercise of this Stock Option and his employer or former employer,
         ("the Agent") is liable to make a payment to the appropriate United
         Kingdom authorities on account of that liability, the Optionee hereby
         irrevocably agrees to indemnify the Agent against such liability and
         hereby appoints the Agent as his agent and attorney to be authorised to
         sell as agent for the Optionee or otherwise procure the sale of
         sufficient of the Shares acquired on the exercise of the Stock Option
         so that the net proceeds of sale are as nearly as possible equal to,
         but not less than, the payment which the Agent is required to pay to
         the appropriate authorities and the costs and expenses incurred by such
         Agent.

12.3     Sub-rule 12.2 does not apply if the Optionee makes alternative
         arrangements to the satisfaction of the Agent to meet the liability
         outlined in sub-rule 12.1.

13.      The Board of Directors may make such alterations to the provisions of
         the Scheme or to the terms governing existing Stock Options granted
         thereunder, as may be permitted by Article 7, Article 18 and Article 19
         of the Plan.


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