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                                                                     Exhibit 4.3

                                TARANTELLA, INC.
                          EMPLOYEE STOCK PURCHASE PLAN
                           (As Amended November 2000)

The following constitute the provisions of the Employee Stock Purchase Plan of
Tarantella, Inc.

1.   Purpose.
     --------

     The purpose of the Plan is to provide employees of the Company and its
Designated Subsidiaries with an opportunity to purchase Common Stock of the
Company through accumulated payroll deductions. It is the intention of the
company to have the Plan qualify as an "Employee Stock Purchase Plan" under
Section 423 of the Internal Revenue Code of 1986, as amended. The provisions of
the Plan, accordingly, shall be construed so as to extend and limit
participation in a manner consistent with the requirements of that section of
the Code.

2.   Definitions.

     a)   "Board" shall mean the Board of Directors of the company.
           -----

     b)   "Code" shall mean the Internal Revenue Code of 1986, as amended.
           ----

     c)   "Common Stock" shall mean the Common Stock of the Company.
           ------------

     d)   "Company" shall mean Tarantella, Inc., a California corporation.
           -------

     e)   "Compensation" shall include all base pay, overtime pay, bonus and
           ------------
          commissions and shall exclude all other amounts.

     f)   "Designated Subsidiaries" shall mean the Subsidiaries which have been
           -----------------------
          designated by the Board from time to time in its sole discretion as
          eligible to participate in the Plan.

     g)   "Employee" shall mean any individual who is a regular employee of the
           --------
          Company for purposes of tax withholding under the Code whose customary
          employment with the Company or any Designated Subsidiary regardless of
          the number of hours worked. For purposes of the Plan, the employment
          relationship shall be treated as continuing intact while the
          individual is on sick leave or other leave of absence approved by the
          Company. Where the period of leave exceeds ninety (90) days and the
          individual's right to employment is not guaranteed either by statute
          or by contract, the employment relationship will be deemed to have
          terminated on the 91st day of such leave.

     h)   "Enrollment Date" shall mean the first day of each Offering Period.
           ---------------

     i)   "Exercise Date" shall mean the last day of each Offering Period.
           -------------

     j)   "Fair Market Value" shall mean, as of any date, the value of Common
           -----------------
          Stock determined as follows:

          i)   If the Common Stock is listed on any established stock exchange
               or a national market system, including without limitation the
               National Market System of the National Association of Securities
               Dealers, Inc. Automated Quotation ("NASDAQ") System, its Fair
               Market Value shall be the closing sale price for the Common Stock
               (or the mean of the closing bid and asked prices, if no sales
               were reported), as quoted on such exchange (or the exchange with
               the greatest volume of trading in Common Stock) or system on the
               date of such determination, as reported in The Wall Street
               Journal or such other source as the Board deems reliable, or;

          ii)  If the Common Stock is quoted on the NASDAQ system (but not on
               the National Market System thereof) or is regularly quoted by a
               recognized securities dealer but selling prices are not reported,
               its Fair Market Value shall be the mean of the closing bid and
               asked prices for the Common Stock on the date of such
               determination, as reported in The Wall Street Journal or such
               other source as the Board deems reliable, or;


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          iii) In the absence of an established market for the Common Stock, the
               Fair Market Value thereof shall be determined in good faith by
               the Board.

          iv)  For purposes of the Enrollment Date under the first Offering
               Period under the Plan, the Fair Market Value of the Common Stock
               shall be the Price to Public as set forth in the final prospectus
               filed with the Securities and Exchange commission pursuant to
               Rule 424 under the Securities Act of 1933, as amended.

     k)   "Offering Period" shall mean a period of approximately six (6) months,
           ---------------
          commencing on the first Trading Day on or after February 1 and
          terminating on the last Trading Day in the period ending the following
          July 31, or commencing on the first Trading Day on or after August 1
          and terminating on the last Trading Day in the period ending the
          following January 31, during which an option granted pursuant to the
          Plan may be exercised. The duration, commencement and termination of
          Offering Periods may be changed pursuant to Section 4 of this Plan.

     l)   "Purchase Price" shall mean an amount equal to 85% of the Fair Market
           --------------
          Value of a share of Common Stock on the Enrollment Date or on the
          Exercise Date, whichever is lower.

     m)   "Reserves" shall mean the number of shares of Common Stock covered by
           --------
          each option under the Plan which have not yet been exercised and the
          number of shares of Common Stock which have been authorized for
          issuance under the Plan but not yet placed under option.

     n)   "Subsidiary" shall mean a corporation, domestic or foreign, of which
           ----------
          not less than 50% of the voting shares are held by the Company or a
          Subsidiary, whether or not such corporation now exists or is hereafter
          organized or acquired by the Company or a Subsidiary.

     o)   "Trading Day" shall mean a day on which national stock exchanges and
           -----------
          the National Association of Securities Dealers Automated Quotation
          (NASDAQ) System are open for trading.

3.   Eligibility.
     -----------

     a)   Any Employee (as defined in Section 2(g)), who shall be employed by
          the Company on a given Enrollment Date shall be eligible to
          participate in the Plan.

     b)   Any provisions of the Plan to the contrary notwithstanding, no
          Employee shall be granted an option under the Plan

          i)   to the extent, immediately after the grant, such Employee (or any
               other person whose stock would be attributed to such Employee
               pursuant to Section 424(d) of the Code) would own capital stock
               of the Company and/or hold outstanding options to purchase such
               stock possessing five percent (5%) or more of the total combined
               voting power or value of all classes of the capital stock of the
               Company or of any Subsidiary, or

          ii)  to the extent his or her rights to purchase stock under all
               employee stock purchase plans of the Company and its subsidiaries
               to accrue at a rate which exceeds Twenty-Five Thousand Dollars
               ($25,000) worth of stock (determined at the fair market value of
               the shares at the time such option is granted) for each calendar
               year in which such option is outstanding at any time.

4.   Offering Periods.
     ----------------

     The Plan shall be implemented by consecutive Offering Periods with a new
     Offering Period commencing on the first Trading Day on or after February 1
     and August 1 each year, or on such other date as the Board shall determine,
     and continuing thereafter until terminated in accordance with Section 19
     hereof. The Board shall have the power to change the duration, commencement
     and termination of Offering Periods with respect to future offerings
     without shareholder approval if such change is announced at least five (5)
     days prior to the scheduled beginning of the first Offering Period to be
     affected thereafter.

5.   Participation.
     -------------

     a)   An eligible Employee may become a participant in the Plan by
          completing a subscription agreement authorizing payroll deductions in
          the form of Exhibit A to this Plan and filing it with the Company's
          payroll office at least ten business days


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          prior to the applicable Enrollment Date, however, a later date, prior
          to the applicable Enrollment Date may be established for all eligible
          Employees to enroll in a given Offering Period.

     b)   Payroll deductions for a participant shall commence on the first
          payroll following the enrollment Date and shall end on the last
          payroll in the Offering Period to which such authorization is
          applicable, unless sooner terminated by the participant as provided in
          Section 10 hereof.

6.   Payroll Deductions.
     ------------------

     a)   At the time a participant files his or her subscription agreement, he
          or she shall elect to have payroll deductions made on each pay day
          during the Offering Period in an amount of at least one percent (1%)
          and not exceeding ten percent (10%) of the Compensation which he or
          she receives on each pay day during the Offering Period, and the
          aggregate of such payroll deductions during the Offering Period shall
          not exceed ten percent (10%) of the participant's Compensation during
          said Offering Period.

     b)   All payroll deductions made for a participant shall be credited to his
          or her account under the Plan and will be withheld in whole
          percentages only. A participant may not make any additional payments
          into such account.

     c)   A participant may discontinue his or her participation in the Plan as
          provided in Section 10 hereof, or may increase or decrease the rate of
          his or her payroll deductions during the Offering Period by completing
          or filing with the Company a new subscription agreement authorizing a
          change in payroll deduction rate. The Board may, in its discretion,
          limit the number of participation rate changes during any Offering
          Period. The change in rate shall be effective with the first full
          payroll period following five (5) business days after the Company's
          receipt of the new subscription agreement unless the Company elects to
          process a given change in participation more quickly. A participant's
          subscription agreement shall remain in effect for successive Offering
          Periods unless terminated as provided in Section 10 hereof.

     d)   Notwithstanding the foregoing, to the extent necessary to comply with
          Section 423(b)(8) of the Code and Section 3(b) hereof, a participant's
          payroll deductions may be decreased to 0% at such time during any
          Offering Period which is scheduled to end during the current calendar
          year (the "Current Offering Period") that the aggregate of all payroll
          deductions which were previously used to purchase stock under the Plan
          in a prior Offering Period which ended during that calendar year plus
          all payroll deductions accumulated with respect to the Current
          Offering Period equal $21,250. Payroll deductions shall recommence at
          the rate provided in such participant' s subscription agreement at the
          beginning of the first Offering Period which is scheduled to end in
          the following calendar year, unless terminated by the participant as
          provided in Section 10 hereof.

     e)   At the time the option is exercised, in whole or in part, or at the
          time some or all of the Company's Common Stock issued under the Plan
          is disposed of, the participant must make adequate provision for the
          Company's federal, state, or other tax withholding obligations, if
          any, which arise upon the exercise of the option or the disposition of
          the Common Stock. At any time, the Company may, but will not be
          obligated to, withhold from the participant's compensation the amount
          necessary for the Company to meet applicable withholding obligations,
          including any withholding required to make available to the Company
          any tax deductions or benefits attributable to sale or early
          disposition of Common Stock by the Employee.

7.   Grant of Option.
     ---------------

     On the Enrollment Date of each Offering Period, each eligible Employee
     participating in such Offering Period shall be granted an option to
     purchase on the Exercise Date of such Offering Period (at the applicable
     Purchase Price) up to a number of shares of the Company's Common Stock
     determined by dividing such Employee's payroll deductions accumulated prior
     to such Exercise Date and retained in the Participant's account as of the
     Exercise Date by the applicable Purchase Price; provided that in no event
     shall an Employee be permitted to purchase during each Offering Period more
     than a number of Shares determined by dividing $12,500 by the Fair Market
     Value of a share of the Company's Common Stock on the Enrollment Date (the
     "Number"), except that for purposes of the first Offering period under the
     Plan, the Number shall be calculated by dividing $25,000 by the Fair Market
     Value of a share of the Company's Common Stock on the Enrollment Date, and
     provided further that all such purchases shall be subject to the
     limitations set forth in Sections 3(b) and 12 hereof. Exercise of the
     option shall occur as provided in Section 8 hereof, unless the participant
     has withdrawn pursuant to Section 10 hereof, and shall expire on the last
     day of the Offering Period.

8.   Exercise of Option.
     ------------------

     Unless a participant withdraws from the Plan as provided in Section 10
     hereof, his or her option for the purchase of shares will be exercised
     automatically on the Exercise Date, and the maximum number of full shares
     subject to option shall be purchased for


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     such participant at the applicable Purchase Price with the accumulated
     payroll deductions in his or her account. No fractional shares will be
     purchased; any payroll deductions accumulated in a participant's account
     which are not sufficient to purchase a full share shall be retained in the
     participant' s account for the subsequent Offering Period, subject to
     earlier withdrawal by the participant as provided in Section 10 hereof. Any
     other moneys left over in a participant's account after the Exercise Date
     shall be returned to the participant. During a participant's lifetime, a
     participant's option to purchase shares hereunder is exercisable only by
     him or her.

9.   Delivery.
     --------

     As promptly as practicable after each Exercise Date on which a purchase of
     shares occurs, the Company shall arrange the delivery to each participant,
     as appropriate, of a certificate representing the shares purchased upon
     exercise of his or her option.

10.  Withdrawal; Termination of Employment.
     -------------------------------------

     a)   A participant may withdraw all but not less than all the payroll
          deductions credited to his or her account and not yet used to exercise
          his or her option under the Plan at any time by giving written notice
          to the Company in the form of Exhibit B to this Plan. All of the
          participant's payroll deductions credited to his or her account will
          be paid to such participant promptly after receipt of notice of
          withdrawal and such participant's option for the Offering Period will
          be automatically terminated, and no further payroll deductions for the
          purchase of shares will be made during the Offering Period. If a
          participant withdraws from an Offering Period, payroll deductions will
          not resume at the beginning of the succeeding Offering Period unless
          the participant delivers to the Company a new subscription agreement.

     b)   Upon a participant's ceasing to be an Employee (as defined in Section
          2(g) hereof ), for any reason he or she will be deemed to have elected
          to withdraw from the Plan and the payroll deductions credited to such
          participant' s account during the Offering Period but not yet used to
          exercise the option will be returned to such participant or, in the
          case of his or her death, to the person or persons entitled thereto
          under Section 14 hereof, and such participant's option will be
          automatically terminated.

     c)   A participant's withdrawal from an Offering Period will not have any
          effect upon his or her eligibility to participate in any similar plan
          which may hereafter be adopted by the Company or in succeeding
          Offering Periods which commence after the termination of the Offering
          Period from which the participant withdraws.

11.  Interest.
     --------

     No interest shall accrue on the payroll deductions of a participant in the
     Plan.

12.  Stock.
     -----

     a)   The maximum number of shares of the Company's Common Stock which shall
          be made available for sale under the Plan shall be 5,000,000 shares,
          subject to adjustment upon changes in capitalization of the Company as
          provided in Section 18 hereof. If on a given Exercise Date the number
          of shares with respect to which options are to be exercised exceeds
          the number of shares then available under the Plan, the Company shall
          make a pro rata allocation of the shares remaining available for
          purchase in as uniform a manner as shall be practicable and as it
          shall determine to be equitable.

     b)   The participant will have no interest or voting right in shares
          covered by his option until such option has been exercised.

     c)   Shares to be delivered to a participant under the Plan will be
          registered in the name of the participant or in the name of the
          participant and his or her spouse.

13.  Administration.
     --------------

     a)   Administrative Body. The Plan shall be administered by the Board or a
          committee of members of the Board appointed by the Board. The Board or
          its committee shall have full and exclusive discretionary authority to
          construe, interpret and apply the terms of the Plan, to determine
          eligibility and to adjudicate all disputed claims filed under the
          Plan. Every finding, decision and determination made by the Board or
          its committee shall, to the full extent permitted by law, be final and
          binding upon all parties.

     b)   Members of the Board who are eligible Employees are permitted to
          participate in the Plan, provided that:


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          i)   Members of the Board who are eligible to participate in the Plan
               may not vote on any matter affecting the administration of the
               Plan or the grant of any option pursuant to the Plan.

          ii)  If a Committee is established to administer the Plan, no member
               of the Board who is eligible to participate in the Plan may be a
               member of the Committee.

     c)   Rule 16b-3 Limitations. Notwithstanding the provisions of Subsection
          (a) of this Section 13, in the event that Rule 16b-3 promulgated under
          the Securities Exchange Act of 1934, as amended (the "Exchange Act"),
          or any successor provision ("Rule 16b-3") provides specific
          requirements for the administrators of plans of this type, the Plan
          shall be only administered by such a body and in such a manner as
          shall comply with the applicable requirements of Rule 16b-3. Unless
          permitted by Rule 16b-3, no discretion concerning decisions regarding
          the Plan shall be afforded to any committee or person that is not
          "disinterested" as that term is used in Rule 16b-3.

14.  Designation of Beneficiary.
     --------------------------

     a)   The beneficiary(ies) designated by the participant to take under the
          life insurance program of the Company, or a beneficiary chosen by a
          participant is written designation to the Company of a beneficiary
          shall receive any shares and cash, if any, from the participant's
          account under the Plan in the event of such participant's death
          subsequent to an Exercise Date on which the option is exercised but
          prior to delivery to such participant of such shares and cash. In
          addition, the same beneficiary(ies) shall receive any cash from the
          participant's account under the Plan in the event of such
          participant's death prior to exercise of the option.

     b)   Such designation of beneficiary may be changed by the participant at
          any time by written notice. In the event of the death of a participant
          and in the absence of a beneficiary validly designated under the Plan
          who is living at the time of such participant's death, the Company
          shall deliver such shares and/or cash to the executor or administrator
          of the estate of the participant, or if no such executor or
          administrator has been appointed (to the knowledge of the Company),
          the Company, in its discretion, may deliver such shares and/or cash to
          the spouse or to any one or more dependents or relatives of the
          participant, or if no spouse, dependent or relative is known to the
          Company, then to such other person as the Company may designate.

15.  Transferability.
     ---------------

     Neither payroll deductions credited to a participant's account nor any
     rights with regard to the exercise of an option or to receive shares under
     the Plan may be assigned, transferred, pledged or otherwise disposed of in
     any way (other than by will, the laws of descent and distribution or as
     provided in Section 14 hereof) by the participant. Any such attempt at
     assignment, transfer, pledge or other disposition shall be without effect,
     except that the Company may treat such act as an election to withdraw funds
     from an Offering Period in accordance with Section 10 hereof.

16.  Use of Funds.
     ------------

     All payroll deductions received or held by the Company under the Plan may
     be used by the Company for any corporate purpose, and the Company shall not
     be obligated to segregate such payroll deductions.

17.  Reports.
     -------

     Individual accounts will be maintained for each participant in the Plan.
     Statements of account will be given to participating Employees at least
     annually, which statements will set forth the amounts of payroll
     deductions, the Purchase Price, the number of shares purchased and the
     remaining cash balance, if any.


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18.  Adjustments Upon Changes in Capitalization.
     ------------------------------------------

     a)   Changes in Capitalization. Subject to any required action by the
          shareholders of the Company, the Reserves as well as the price per
          share of Common Stock covered by each option under the Plan which has
          not yet been exercised shall be proportionately adjusted for any
          increase or decrease in the number of issued shares of Common Stock
          resulting from a stock split, reverse stock split, stock dividend,
          combination or reclassification of the Common Stock, or any other
          increase or decrease in the number of shares of Common Stock effected
          without receipt of consideration by the Company; provided, however,
          that conversion of any convertible securities of the Company shall not
          be deemed to have been "effected without receipt of consideration".
          Such adjustment shall be made by the Board, whose determination in
          that respect shall be final, binding and conclusive. Except as
          expressly provided herein, no issuance by the Company of shares of
          stock of any class, or securities convertible into shares of stock of
          any class, shall affect, and no adjustment by reason thereof shall be
          made with respect to, the number or price of shares of Common Stock
          subject to an option.

     b)   Dissolution or Liquidation. In the event of the proposed dissolution
          or liquidation of the Company, the Offering Period will terminate
          immediately prior to the consummation of such proposed action, unless
          otherwise provided by the Board.

     c)   Merger or Asset Sale. In the event of a proposed sale of all or
          substantially all of the assets of the Company, or the merger of the
          Company with or into another corporation, each option under the Plan
          shall be assumed or an equivalent option shall be substituted by such
          successor corporation or a parent or subsidiary of such successor
          corporation, unless the Board determines, in the exercise of its sole
          discretion and in lieu of such assumption or substitution, to shorten
          the Offering Period then in progress by setting a new Exercise Date
          (the "New Exercise Date") or to cancel each outstanding right to
          purchase and refund all sums collected from participants during the
          Offering Period then in progress. If the Board shortens the Offering
          Period then in progress in lieu of assumption or substitution in the
          event of a merger or sale of assets, the Board shall notify each
          participant in writing, at least ten (10) business days prior to the
          New Exercise Date, that the Exercise Date for his option has been
          changed to the New Exercise Date and that his option will be exercised
          automatically on the New Exercise Date, unless prior to such date he
          has withdrawn from the Offering Period as provided in Section 10
          hereof. For purposes of this paragraph, an option granted under the
          Plan shall be deemed to be assumed if, following the sale of assets or
          merger, the option confers the right to purchase, for each share of
          option stock subject to the option immediately prior to the sale of
          assets or merger, the consideration (whether stock, cash or other
          securities or property) received in the sale of assets or merger by
          holders of Common Stock for each share of Common Stock held on the
          effective date of the transaction (and if such holders were offered a
          choice of consideration, the type of consideration chosen by the
          holders of a majority of the outstanding shares of Common Stock);
          provided, however, that if such consideration received in the sale of
          assets or merger was not solely common stock of the successor
          corporation or its parent (as defined in Section 424(e) of the Code),
          the Board may, with the consent of the successor corporation and the
          participant, provide for the consideration to be received upon
          exercise of the option to be solely common stock of the successor
          corporation or its parent equal in fair market value to the per share
          consideration received by holders of Common Stock and the sale of
          assets or merger.

     d)   The Board may, if it so determines in the exercise of its sole
          discretion, also make provision for adjusting the Reserves, as well as
          the price per share of Common Stock covered by each outstanding
          option, in the event the Company effects one or more reorganizations,
          recapitalization, rights offerings or other increases or reductions of
          shares of its outstanding Common Stock, and in the event of the
          Company being consolidated with or merged into any other corporation.

19.  Amendment or Termination.
     ------------------------

     a)   The Board of Directors of the Company may at any time and for any
          reason terminate or amend the Plan. Except as provided in Section 18
          hereof, no such termination can affect options previously granted,
          provided that an Offering Period may be terminated by the Board of
          Directors on any Exercise Date if the Board determines that the
          termination of the Plan is in the best interests of the Company and
          its shareholders. Except as provided in Section 18 hereof, no
          amendment may make any change in any option theretofore granted which
          adversely affects the rights of any participant. To the extent
          necessary to comply with Rule 16b-3 or under Section 423 of the Code
          (or any successor rule or provision or any other applicable law or
          regulation), the Company shall obtain shareholder approval in such a
          manner and to such a degree as required.

     b)   Without shareholder consent and without regard to whether any
          participant rights may be considered to have been "adversely
          affected," the Board (or its committee) shall be entitled to change
          the Offering Periods, limit the frequency and/or number of changes in
          the amount withheld during an Offering Period, establish the exchange
          ratio applicable to amounts withheld in a currency other than U.S.
          dollars, permit payroll withholding in excess of the amount designated
          by a


                                     Page 6

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          participant in order to adjust for delays or mistakes in the Company's
          processing of properly completed withholding elections, establish
          reasonable waiting and adjustment periods and/or accounting and
          crediting procedures to ensure that amounts applied toward the
          purchase of Common Stock for each participant properly correspond with
          amounts withheld from the participant's Compensation, and establish
          such other limitations or procedures as the Board (or its committee)
          determines in its sole discretion advisable which are consistent with
          the Plan.

20.  Notices.
     -------

     All notices or other communications by a participant to the Company under
     or in connection with the Plan shall be deemed to have been duly given when
     received in the form specified by the Company at the location, or by the
     person, designated by the Company for the receipt thereof.

21.  Conditions Upon Issuance of Shares.
     ----------------------------------

     Shares shall not be issued with respect to an option unless the exercise of
     such option and the issuance and delivery of such shares pursuant thereto
     shall comply with all applicable provisions of law, domestic or foreign,
     including, without limitation, the Securities Act of 1933, as amended, the
     Securities Exchange Act of 1934, as amended, the rules and regulations
     promulgated thereunder, and the requirements of any stock exchange upon
     which the shares may then be listed, and shall be further subject to the
     approval of counsel for the Company with respect to such compliance.

     As a condition to the exercise of an option, the Company may require the
     person exercising such option to represent and warrant at the time of any
     such exercise that the shares are being purchased only for investment and
     without any present intention to sell or distribute such shares if, in the
     opinion of counsel for the Company, such a representation is required by
     any of the aforementioned applicable provisions of law.

22.  Term of Plan.
     ------------

     The Plan shall become effective upon the earlier to occur of its adoption
     by the Board of Directors or its approval by the shareholders of the
     Company. It shall continue in effect for a term of ten (10) years unless
     sooner terminated under Section 19 hereof.

23.  Additional Restrictions of Rule 16b-3.
     -------------------------------------

     The terms and conditions of options granted hereunder to, and the purchase
     of shares by, persons subject to Section 16 of the Exchange Act shall
     comply with the applicable provisions of Rule 16b-3. This Plan shall be
     deemed to contain, and such options shall contain, and the shares issued
     upon exercise thereof shall be subject to, such additional conditions and
     restrictions as may be required by Rule 16b-3 to qualify for the maximum
     exemption from Section 16 of the exchange Act with respect to Plan
     transactions.


                                     Page 7