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                                                                  EXHIBIT 99.4


                             DOT HILL SYSTEMS CORP.

             2000 AMENDED AND RESTATED EMPLOYEE STOCK PURCHASE PLAN

               ADOPTED BY THE BOARD OF DIRECTORS ON MARCH 9, 2000
                     APPROVED BY STOCKHOLDERS ON MAY 8, 2000
                          EFFECTIVE DATE: MARCH 9, 2000
                         TERMINATION DATE: MARCH 8, 2010

1.     PURPOSE.

       (a) The purpose of this 2000 Amended and Restated Employee Stock
Purchase Plan (the "PLAN") is to provide a means by which employees of DOT
HILL SYSTEMS CORP., a New York corporation (the "COMPANY"), and its
Affiliates, as defined in subparagraph 1(c), which are designated as provided
in subparagraph 2(b), may be given an opportunity to purchase stock of the
Company.

       (b) This Plan hereby amends and restates the Company's 1997 Employee
Stock Purchase Plan (the "FORMER PLAN"), and the stock awards granted under
the Former Plan shall be governed by the provisions of this Plan; PROVIDED,
HOWEVER, that (i) to the extent necessary to preserve the tax treatment of
the stock awards granted under the Former Plan, as provided under the Code
(defined below in subparagraph 1(c)), this Plan shall not amend or modify
said outstanding stock awards grants; and (ii) outstanding stock awards
granted under the Former Plan shall receive the same benefits, subject to
clause (i) of this proviso, but not the disadvantages (if any) under this
Plan.

       (c) The word "AFFILIATE" as used in the Plan means any parent
corporation or subsidiary corporation of the Company, as those terms are
defined in Sections 424(e) and (f), respectively, of the Internal Revenue
Code of 1986, as amended (the "CODE").

       (d) The Company, by means of the Plan, seeks to retain the services of
its employees, to secure and retain the services of new employees, and to
provide incentives for such persons to exert maximum efforts for the success
of the Company.

       (e) The Company intends that the rights to purchase stock of the
Company granted under the Plan be considered options issued under an
"employee stock purchase plan" as that term is defined in Section 423(b) of
the Code.

2.     ADMINISTRATION.

       (a) The Plan shall be administered by the Board of Directors of the
Company (the "BOARD") unless and until the Board delegates administration to
a Committee, as provided in subparagraph 2(c). Whether or not the Board has
delegated administration, the Board shall have the final power to determine
all questions of policy and expediency that may arise in the administration
of the Plan.

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       (b)  The Board shall have the power, subject to, and within the
limitations of, the express provisions of the Plan:

            (i)   To determine when and how rights to purchase stock of the
Company shall be granted and the provisions of each offering of such rights
(which need not be identical).

            (ii)  To designate from time to time which Affiliates of the
Company shall be eligible to participate in the Plan.

            (iii) To construe and interpret the Plan and rights granted under
it, and to establish, amend and revoke rules and regulations for its
administration. The Board, in the exercise of this power, may correct any
defect, omission or inconsistency in the Plan, in a manner and to the extent
it shall deem necessary or expedient to make the Plan fully effective.

            (iv)  To amend the Plan as provided in paragraph 13.

            (v)   Generally, to exercise such powers and to perform such acts
as the Board deems necessary or expedient to promote the best interests of
the Company and its Affiliates.

       (c)  The Board may delegate administration of the Plan to a Committee
composed of not fewer than two (2) members of the Board (the "COMMITTEE"). If
administration is delegated to a Committee, the Committee shall have, in
connection with the administration of the Plan, the powers theretofore
possessed by the Board, subject, however, to such resolutions, not
inconsistent with the provisions of the Plan, as may be adopted from time to
time by the Board. The Board may abolish the Committee at any time and revest
in the Board the administration of the Plan.

       (d)  Any interpretation of the Plan by the Board of any decision made
by it under the Plan shall be final and binding on all persons.

3.     SHARES SUBJECT TO THE PLAN.

       (a)  Subject to the provisions of paragraph 12 relating to adjustments
upon changes in stock, the stock that may be sold pursuant to rights granted
under the Plan shall not exceed in the aggregate of seven hundred fifty
thousand (750,000) shares of the Company's common stock (the "COMMON STOCK")
plus an annual increase to be added on the day of each Annual Stockholders'
Meeting beginning with the Annual Stockholders' Meeting in 2001, equal to the
lesser of (i) 100,000 shares, or (ii) an amount determined by the Board. If
any right granted under the Plan shall for any reason terminate without
having been exercised, the Common Stock not purchased under such right shall
again become available for the Plan.

       (b)  The stock subject to the Plan may be unissued shares or
reacquired shares, bought on the market or otherwise.

4.     GRANT OF RIGHTS; OFFERING.

       (a)  The Board or the Committee may from time to time grant or provide
for the grant of rights to purchase Common Stock of the Company under the
Plan to eligible employees (an

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"OFFERING") on a date or dates (the "OFFERING DATE(S)") selected by the Board
or the Committee. Each Offering shall be in such form and shall contain such
terms and conditions as the Board or the Committee shall deem appropriate,
which shall comply with the requirements of Section 423(b)(5) of the Code
that all employees granted rights to purchase stock under the Plan shall have
the same rights and privileges. The provisions of separate Offerings need not
be identical, but each Offering shall include (through incorporation of the
provisions of this Plan by reference in the Offering or otherwise) the period
during which the Offering shall be effective, which period shall not exceed
twenty-seven (27) months beginning with the Offering Date, and the substance
of the provisions contained in paragraphs 5 through 8, inclusive.

       (b)  If an employee has more than one right outstanding under the
Plan, unless he or she otherwise indicates in agreements or notices delivered
hereunder: (1) each agreement or notice delivered by that employee will be
deemed to apply to all of his or her rights under the Plan, and (2) a right
with a lower exercise price (or an earlier-granted right, if two rights have
identical exercise prices), will be exercised to the fullest possible extent
before a right with a higher exercise price (or a later-granted right, if two
rights have identical exercise prices) will be exercised.

5.      ELIGIBILITY.

       (a)  Rights may be granted only to employees of the Company or, as the
Board or the Committee may designate as provided in subparagraph 2(b), to
employees of any Affiliate of the Company. Except as provided in subparagraph
5(b), an employee of the Company or any Affiliate shall not be eligible to be
granted rights under the Plan, unless, on the Offering Date, such employee is
in the employ of the Company and has been in the employ of the Company or any
Affiliate for such continuous period preceding such grant as the Board or the
Committee may require, but in no event shall the required period of
continuous employment be greater than two (2) years. In addition, unless
otherwise determined by the Board or the Committee and set forth in the terms
of the applicable Offering, no employee of the Company or any Affiliate shall
be eligible to be granted rights under the Plan, unless, on the Offering
Date, such employee's customary employment with the Company or such Affiliate
is for at least twenty (20) hours per week and at least three (3) months per
calendar year.

       (b)  Each person who, during the course of an Offering, first becomes
an eligible employee of the Company or designated Affiliate shall not then be
eligible to be granted rights under such Offering.

       (c)  No employee shall be eligible for the grant of any rights under
the Plan if, immediately after any such rights are granted, such employee
owns stock possessing five percent (5%) or more of the total combined voting
power or value of all classes of stock of the Company or of any Affiliate.
For purposes of this subparagraph 5(c), the rules of Section 424(d) of the
Code shall apply in determining the stock ownership of any employee, and
stock which such employee may purchase under all outstanding rights and
options shall be treated as stock owned by such employee.

       (d)  An eligible employee may be granted rights under the Plan only if
such rights, together with any other rights granted under "employee stock
purchase plans" of the Company

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and any Affiliates, as specified by Section 423(b)(8) of the Code, do not
permit such employee's rights to purchase stock of the Company or any
Affiliate to accrue at a rate which exceeds twenty-five thousand dollars
($25,000) of fair market value of such stock (determined at the time such
rights are granted) for each calendar year in which such rights are
outstanding at any time.

       (e)  Officers of the Company and any designated Affiliate shall be
eligible to participate in Offerings under the Plan, PROVIDED, HOWEVER, that
the Board may provide in an Offering that certain employees who are highly
compensated employees within the meaning of Section 423(b)(4)(D) of the Code
shall not be eligible to participate.

6.     RIGHTS; PURCHASE PRICE.

       (a)  On each Offering Date, each eligible employee, pursuant to an
Offering made under the Plan, shall be granted the right to purchase up to
the number of shares of Common Stock of the Company purchasable with a
percentage designated by the Board or the Committee not exceeding fifteen
percent (15%) of such employee's Earnings (as defined in subparagraph 7(a))
during the period which begins on the Offering Date (or such later date as
the Board or the Committee determines for a particular Offering) and ends on
the date stated in the Offering, which date shall be no later than the end of
the Offering. The Board or the Committee shall establish one or more dates
during an Offering (the "PURCHASE DATE(S)") on which rights granted under the
Plan shall be exercised and purchases of Common Stock effected in accordance
with such Offering.

       (b)  In connection with each Offering made under this Plan, the Board
or the Committee shall specify a maximum number of shares which may be
purchased by any employee as well as a maximum aggregate number of shares
which may be purchased by all eligible employees pursuant to such Offering.
In addition, in connection with each Offering which contains more than one
Purchase Date, the Board or the Committee may specify a maximum aggregate
number of shares which may be purchased by all eligible employees on any
given Purchase Date under the Offering. If the aggregate purchase of shares
upon exercise of rights granted under the Offering would exceed any such
maximum aggregate number, the Board or the Committee shall make a pro rata
allocation of the shares available in as nearly a uniform manner as shall be
practicable and as it shall deem to be equitable.

       (c)  The purchase price of stock acquired pursuant to rights granted
under the Plan shall be not less than the lesser of:

            (i)   an amount equal to eighty-five percent (85%) of the fair
market value of the stock on the Offering Date; or

            (ii)  an amount equal to eighty-five percent (85%) of the fair
market value of the stock on the Purchase Date.

7.     PARTICIPATION; WITHDRAWAL; TERMINATION.

       (a)  An eligible employee may become a participant in the Plan
pursuant to an Offering by delivering a participation agreement to the
Company within the time specified in the Offering, in such form as the
Company provides; PROVIDED, HOWEVER, that an eligible employee

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shall be entitled to participate in no more than one (1) Offering at any
time. Each such agreement shall authorize payroll deductions of up to the
maximum percentage specified by the Board or the Committee of such employee's
Earnings during the Offering. "EARNINGS" is defined as an employee's regular
salary or wages (including amounts thereof elected to be deferred by the
employee, that would otherwise have been paid, under any cash or deferred
arrangement established by the Company), which shall include commissions and
overtime pay, but shall exclude bonuses, incentive pay, profit sharing, other
remuneration paid directly to the employee, the cost of employee benefits
paid for by the Company or an Affiliate, education or tuition reimbursements,
imputed income arising under any group insurance or benefit program,
traveling expenses, business and moving expense reimbursements, income
received in connection with stock options, contributions made by the Company
or an Affiliate under any employee benefit plan, and similar items of
compensation. The payroll deductions made for each participant shall be
credited to an account for such participant under the Plan and shall be
deposited with the general funds of the Company or an Affiliate. A
participant may reduce (including to zero) or increase such payroll
deductions after the beginning of any Offering only as provided for in the
Offering. A participant may not make additional payments into his or her
account.

       (b)  At any time during an Offering, a participant may terminate his
or her payroll deductions under the Plan and withdraw from the Offering by
delivering to the Company a notice of withdrawal in such form as the Company
provides. Such withdrawal may be elected at any time prior to the end of the
Offering except as provided by the Board or the Committee in the Offering.
Upon such withdrawal from the Offering by a participant, the Company shall
distribute to such participant all of his or her accumulated payroll
deductions (reduced to the extent, if any, such deductions have been used to
acquire stock for the participant) under the Offering, without interest, and
such participant's interest in that Offering shall be automatically
terminated. A participant's withdrawal from an Offering will have no effect
upon such participant's eligibility to participate in any other Offerings
under the Plan but such participant will be required to deliver a new
participation agreement in order to participate in subsequent Offerings under
the Plan. A reduction of payroll deductions to zero shall not, by itself,
constitute a withdrawal from an Offering.

       (c)  Rights granted pursuant to any Offering under the Plan shall
terminate immediately upon cessation of any participating employee's
employment with the Company and any designated Affiliate, for any reason, and
the Company shall distribute to such terminated employee all of his or her
accumulated payroll deductions (reduced to the extent, if any, such
deductions have been used to acquire stock for the terminated employee),
under the Offering, without interest.

       (d)  Rights granted under the Plan shall not be transferable, and,
except as provided in paragraph 14, shall be exercisable only by the person
to whom such rights are granted.

8.     EXERCISE.

       (a)  On each Purchase Date specified in the relevant Offering, each
participant's accumulated payroll deductions (without any increase for
interest) will be applied to the purchase of whole shares of stock of the
Company, up to the maximum number of shares

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permitted pursuant to the terms of the Plan and the applicable Offering, at
the purchase price specified in the Offering. No fractional shares shall be
issued upon the exercise of rights granted under the Plan. The amount, if
any, of accumulated payroll deductions remaining in each participant's
account after the purchase of shares on the final Purchase Date of an
Offering shall be distributed to the participant after such final Purchase
Date, without interest.

       (b)  No rights granted under the Plan may be exercised to any extent
unless the Plan (including rights granted thereunder) is covered by an
effective registration statement pursuant to the Securities Act of 1933, as
amended (the "SECURITIES ACT") and the Plan is in material compliance with
all applicable state, foreign and other securities and other laws applicable
to the Plan. If on a Purchase Date in any Offering hereunder the Plan is not
so registered, no rights granted under the Plan or any Offering shall be
exercised on such Purchase Date, and the Purchase Date shall be delayed until
the Plan is subject to such an effective registration statement and in such
compliance, except that the Purchase Date shall not be delayed more than
twelve (12) months and the Purchase Date shall in no event be more than
twenty-seven (27) months from the Offering Date. If on the Purchase Date of
any Offering hereunder, as delayed to the maximum extent permissible, the
Plan is not registered and in such compliance, no rights granted under the
Plan or any Offering shall be exercised and all payroll deductions
accumulated during the Offering (reduced to the extent, if any, such
deductions have been used to acquire stock) shall be distributed to the
participants, without interest.

9.     COVENANTS OF THE COMPANY.

       (a)  During the terms of the rights granted under the Plan, the
Company shall keep available at all times the number of shares of stock
required to satisfy such rights.

       (b)  The Company shall seek to obtain from each regulatory commission
or agency having jurisdiction over the Plan such authority as may be required
to issue and sell shares of stock upon exercise of the rights granted under
the Plan. If, after reasonable efforts, the Company is unable to obtain from
any such regulatory commission or agency the authority which counsel for the
Company deems necessary for the lawful issuance and sale of stock under the
Plan, the Company shall be relieved from any liability for failure to issue
and sell stock upon exercise of such rights unless and until such authority
is obtained.

10.    USE OF PROCEEDS FROM STOCK.

       Proceeds from the sale of stock pursuant to rights granted under the
Plan shall constitute general funds of the Company.

11.    RIGHTS AS A STOCKHOLDER.

       A participant shall not be deemed to be the holder of, or to have any
of the rights of a holder with respect to, any shares subject to rights
granted under the Plan unless and until the participant's stockholdings
acquired upon exercise of rights under the Plan are recorded in the books of
the Company.

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12.    ADJUSTMENTS UPON CHANGES IN STOCK.

       (a)  If any change is made in the stock subject to the Plan, or
subject to any rights granted under the Plan (through merger, consolidation,
reorganization, recapitalization, stock dividend, dividend in property other
than cash, stock split, liquidating dividend, combination of shares, exchange
of shares, change in corporate structure or otherwise), the Plan and
outstanding rights will be appropriately adjusted in the class(es) and
maximum number of shares subject to the Plan and the class(es) and number of
shares and price per share of stock subject to outstanding rights.

       (b)  In the event of: (1) a dissolution or liquidation of the Company;
(2) a merger or consolidation in which the Company is not the surviving
corporation; (3) a reverse merger in which the Company is the surviving
corporation but the shares of the Company's Common Stock outstanding
immediately preceding the merger are converted by virtue of the merger into
other property, whether in the form of securities, cash or otherwise; or (4)
any other capital reorganization, in which more than fifty percent (50%) of
the shares of the Company entitled to vote are exchanged, then, as determined
by the Board in its sole discretion (i) any surviving corporation may assume
outstanding rights or substitute similar rights for those under the Plan,
(ii) such rights may continue in full force and effect, or (iii)
participants' accumulated payroll deductions may be used to purchase Common
Stock immediately prior to the transaction described above and the
participants' rights under the ongoing Offering terminates.

13.    AMENDMENT OF THE PLAN.

       (a)  The Board at any time, and from time to time, may amend the Plan.
However, except as provided in paragraph 12 relating to adjustments upon
changes in stock, no amendment shall be effective unless approved by the
stockholders of the Company within twelve (12) months before or after the
adoption of the amendment, where the amendment will:

            (i)   Increase the number of shares reserved for rights under the
Plan;

            (ii)  Modify the provisions as to eligibility for participation
in the Plan (to the extent such modification requires stockholder approval in
order for the Plan to obtain employee stock purchase plan treatment under
Section 423 of the Code or to comply with the requirements of Rule 16b-3
promulgated under the Securities Exchange Act of 1934, as amended ("RULE
16b-3")); or

            (iii) Modify the Plan in any other way if such modification requires
stockholder approval in order for the Plan to obtain employee stock purchase
plan treatment under Section 423 of the Code or to comply with the requirements
of Rule 16b-3.

It is expressly contemplated that the Board may amend the Plan in any respect
the Board deems necessary or advisable to provide eligible employees with the
maximum benefits provided or to be provided under the provisions of the Code
and the regulations promulgated thereunder relating to employee stock
purchase plans and/or to bring the Plan and/or rights granted under it into
compliance therewith.

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       (b)  Rights and obligations under any rights granted before amendment
of the Plan shall not be impaired by any amendment of the Plan, except with
the consent of the person to whom such rights were granted or except as
necessary to comply with any laws or governmental regulation.

14.    DESIGNATION OF BENEFICIARY.

       (a)  A participant may file a written designation of a beneficiary who
is to 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 the end
of an Offering but prior to delivery to him of such shares and cash. In
addition, a participant may file a written designation of a beneficiary who
is to receive any cash from the participant's account under the Plan in the
event of such participant's death during an Offering.

       (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.    TERMINATION OR SUSPENSION OF THE PLAN.

       (a)  The Board may suspend or terminate the Plan at any time. Unless
sooner terminated, the Plan shall terminate on the day before the tenth
(10th) anniversary of the date the Plan is adopted by the Board or approved
by the stockholders of the Company, whichever is earlier. No rights may be
granted under the Plan while the Plan is suspended or after it is terminated.

       (b)  Rights and obligations under any rights granted while the Plan is
in effect shall not be impaired by suspension or termination of the Plan,
except as expressly provided in the Plan or with the consent of the person to
whom such rights were granted or except as necessary to comply with any laws
or governmental regulation.

16.    EFFECTIVE DATE OF PLAN.

       The Plan shall become effective on the date that the Plan is adopted
by the Board, but no rights granted under the Plan shall be exercised unless
and until the Plan has been approved by the stockholders of the Company,
which approval shall be within twelve (12) months before or after the date
the Plan is adopted by the Board.

17.    CHOICE OF LAW.

       All questions concerning the construction, validity and interpretation
of this Plan shall be governed by the law of the State of California, without
regard to such state's conflict of laws rules.