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                                                                 EXHIBIT 10.21.2

McDATA CORPORATION

                          EMPLOYEE STOCK PURCHASE PLAN


         1. Purpose and Scope of Plan. The purpose of this McDATA Corporation
Employee Stock Purchase Plan (the "Plan") is to provide the employees of McDATA
Corporation (the "Company") and its subsidiaries with an opportunity to acquire
a proprietary interest in the Company through the purchase of its common stock
and, thus, to develop a stronger incentive to work for the continued success of
the Company. The Plan is intended to be an "employee stock purchase plan" within
the meaning of Section 423 of the Internal Revenue Code, and shall be
interpreted and administered in a manner consistent with such intent.

         2. Definitions.

                  2.1. The terms defined in this section are used (and
         capitalized) elsewhere in this Plan:

                  (a) "Affiliate" means each domestic or foreign corporation
                  that is a "parent corporation" or "subsidiary corporation" of
                  the Company, as defined in Sections 424(e) and 424(f) of the
                  Code or any successor provision and whose participation in the
                  Plan the Board of Directors has expressly approved.

                  (b) "Board of Directors" means the Board of Directors of the
                  Company.

                  (c) "Code" means the Internal Revenue Code of 1986, as amended
                  from time to time.

                  (d) "Committee" means three or more Disinterested Persons
                  designated by the Board of Directors to administer the Plan
                  under Section 13.

                  (e) "Common Stock" means the par value $.01 per share Class B
                  common stock of the Company.

                  (f) "Company" means McDATA Corporation.

                  (g) "Compensation" means the gross cash compensation
                  (including wage, salary, commission, bonus, and overtime
                  earnings) paid by the Company or any Affiliate to a
                  Participant in accordance with the terms of employment.

                  (h) "Disinterested Person" means a member of the Board of
                  Directors who is considered a disinterested person within the
                  meaning of Exchange Act Rule 16b-3 or any successor
                  definition.

                  (i) "Eligible Employee" means any employee of the Company or
                  an Affiliate whose customary employment is at least 24 hours
                  per week; provided, however, that "Eligible Employee" shall
                  not include any person who would be deemed, for purposes of
                  Section 423(b)(3) of the Code, to own stock possessing 5% or
                  more of the total combined voting power or value of all
                  classes of stock of the Company.

                  (j) "Exchange Act" means the Securities Exchange Act of 1934,
                  as amended from time to time.

                  (k) "Fair Market Value" of a share of Common Stock as of any
                  date means, if the Company's Common Stock is listed on a
                  national securities exchange or traded in the national market
                  system, the closing price for such Common Stock on such
                  exchange or market on said date, or, if no sale has been made
                  on such exchange or market on said date, on the last preceding
                  day on which any sale shall have been made. If such
                  determination of Fair Market Value is not consistent with the
                  then current regulations of the Secretary of the Treasury
                  applicable to plans intended to qualify as an "employee stock
                  purchase plan" within the meaning of Section 423(b) of


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                  the Code, however, Fair Market Value shall be determined in
                  accordance with such regulations. The determination of Fair
                  Market Value shall be subject to adjustment as provided in
                  Section 14.

                  (l) "Participant" means an Eligible Employee who has elected
                  to participate in the Plan in the manner set forth in Section
                  4.

                  (m) "Plan" means this McDATA Corporation Employee Stock
                  Purchase Plan, as amended from time to time.

                  (n) "Purchase Period" means, for the first purchase period,
                  starting August 15, 2002 and ending at the end of January
                  2003, and thereafter a six-month period ending on the last day
                  of July or January of each year or such other period of time
                  as may be adopted by the Committee.

                  (o) "Recordkeeping Account" means the account maintained in
                  the books and records of the Company recording the amount
                  withheld from each Participant through payroll deductions made
                  under the Plan.

         3. Scope of the Plan. Shares of Common Stock may be sold by the Company
to Eligible Employees at any time after this Plan has been approved by the
shareholders of the Company, but not more than 1,200,000 shares of Common Stock
(subject to adjustment as provided in Section 14) shall be sold to Eligible
Employees pursuant to this Plan. All sales of Common Stock pursuant to this Plan
shall be subject to the same terms, conditions, rights and privileges.

         4. Eligibility and Participation. To be eligible to participate in the
Plan for a given Purchase Period, an employee must be an Eligible Employee on
the first day of such Purchase Period. An Eligible Employee may elect to
participate in the Plan by filing an election form with the Company before the
first day of a Purchase Period that authorizes regular payroll deductions from
Compensation beginning with the first payday in such Purchase Period and
continuing until the Plan is terminated or the Eligible Employee withdraws from
the Plan, modifies his or her authorization, or ceases to be an Eligible
Employee, as hereinafter provided.

         5. Amount of Common Stock Each Eligible Employee May Purchase.

                  5.1. Subject to the provisions of this Plan, each Eligible
         Employee shall be offered the right to purchase on the last day of the
         Purchase Period the maximum number of shares of Common Stock (including
         fractional shares if allowed by the Company) that can be purchased at
         the price specified in Section 5.2 with the entire balance in the
         Participant's Recordkeeping Account; provided, however, that the Fair
         Market Value (determined on the first day of any Purchase Period) of
         shares of Common Stock that may be purchased by a Participant during
         such Purchase Period shall not exceed the excess, if any, of (i)
         $25,000 over (ii) the Fair Market Value (determined on the first day of
         the relevant Purchase Period) of shares of Common Stock previously
         acquired by the Participant in any prior Purchase Period during such
         calendar year. Notwithstanding the foregoing, no Eligible Employee
         shall be granted an option to acquire shares of Common Stock under this
         Plan which permits the Eligible Employee's rights to purchase shares of
         Common Stock under this Plan and all employee stock purchase plans
         (within the meaning of Section 423(b) of the Code), if any, of the
         Company and its Affiliates to accrue at a rate which exceeds $25,000 of
         Fair Market Value (determined at the time such option is granted) for
         each calendar year in which such option is outstanding at any time. If
         the purchases by all Participants would otherwise cause the aggregate
         number of shares of Common Stock to be sold under the Plan to exceed
         the number specified in Section 3, however, each Participant shall be
         allocated a ratable portion of the maximum number of shares of Common
         Stock which may be sold.

                  5.2. The purchase price of each share of Common Stock sold
         pursuant to this Plan will be the lesser of:

                  (a) 85% of the Fair Market Value of such share on the first
                  day of the Purchase Period, or

                  (b) 85% of the Fair Market Value of such share on the last day
                  of the Purchase Period.


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         6. Method of Participation.

                  6.1. The Company shall give notice to each Eligible Employee
         of the opportunity to purchase shares of Common Stock pursuant to this
         Plan and the terms and conditions for such offering. Such notice is
         subject to revision by the Company at any time prior to the date of
         purchase of such shares. The Company contemplates that for tax purposes
         the first day of a Purchase Period will be the date of the offering of
         such shares.

                  6.2. Each Eligible Employee who desires to participate in the
         Plan for a Purchase Period shall signify his or her election to do so
         by signing and filing with the Company an election form developed by
         the Committee. An Eligible Employee may elect to have any whole percent
         of Compensation withheld as a payroll deduction, but not exceeding ten
         percent (10%) per pay period. An election to participate in the Plan
         and to authorize payroll deductions as described herein must be made
         before the first day of a Purchase Period. The election shall be
         effective for the first pay period in the Purchase Period immediately
         following the filing of such election form and shall remain in effect
         until the Plan is terminated or such Participant withdraws from the
         Plan, modifies his or her authorization, or ceases to be an Eligible
         Employee, as hereinafter provided.

         7. Recordkeeping Account.

                  7.1. The Company shall maintain a Recordkeeping Account for
         each Participant. Payroll deductions pursuant to Section 6 will be
         credited to such Recordkeeping Accounts on each payday.

                  7.2. No interest will be credited to a Participant's
         Recordkeeping Account.

                  7.3. The Recordkeeping Account is established solely for
         accounting purposes, and all amounts credited to the Recordkeeping
         Account will remain part of the general assets of the Company.

                  7.4. A Participant may not make any separate cash payment into
         a Recordkeeping Account.

         8. Right to Adjust Participation; Withdrawals from Recordkeeping
Account.

                  8.1. A Participant may at any time withdraw from the Plan. If
         a Participant withdraws from the Plan, the Company will pay to the
         Participant in cash the entire balance in such Participant's
         Recordkeeping Account and no further deductions will be made from the
         Participant's Compensation during such Purchase Period. A Participant
         who withdraws from the Plan will not be eligible to reenter the Plan
         until the next succeeding Purchase Period.

                  8.2. Except as otherwise provided in Section 8.1, a
         Participant may only increase or decrease the deductions from his or
         her Compensation as of the first pay period in any Purchase Period.

                  8.3. Notification of a Participant's election (i) to withdraw
         from the Plan and terminate deductions or (ii) to increase or decrease
         deductions shall be made by signing and filing with the Company an
         appropriate form developed by the Committee.

         9. Termination of Employment. If the employment of a Participant is
terminated for any reason, including death, disability, or retirement, the
entire balance in the Participant's Recordkeeping Account will be refunded in
cash to the Participant within 15 days after the date of termination of
employment.

         10. Purchase of Shares.

                  10.1. As of the last day of the Purchase Period, the entire
         balance in each Participant's Recordkeeping Account will be used to
         purchase shares (including fractional shares) of Common Stock (subject
         to the limitations of Section 5) unless the Participant has filed an
         appropriate form with the Company in advance of that date (which elects
         to receive all or a portion of the balance in cash). Any amount in a
         Participant's Recordkeeping Account that is not used to purchase shares
         pursuant to this Section 10.1 will be refunded to the Participant.


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                  10.2. Promptly after the end of each Purchase Period, a
         certificate for the number of shares of Common Stock purchased by all
         Participants shall be issued and delivered to an agent selected by the
         Company. The agent will hold such certificate for the benefit of all
         Participants who have purchased shares of Common Stock and will
         maintain an account for each Participant reflecting the number of
         shares (including fractional shares if allowed by the Company) credited
         to the account of each Participant. Each Participant will be entitled
         to direct the voting of all shares credited to such Participant's
         account by the agent. Each Participant may also direct such agent to
         sell such shares and distribute the net proceeds of such sale to the
         Participant. At any time after the Participant has satisfied the
         minimum holding period requirements established by Section 423(a)(1) of
         the Code, a Participant may request from the agent a certificate
         representing the shares of Common Stock credited to the Participant's
         account, in which case the agent shall transfer a certificate for such
         shares directly to the Participant; provided, however, that the agent
         shall not be required to issue a certificate representing a fractional
         share and may instead pay the Participant a cash amount representing
         the fair market value of such fractional share.

         11. Rights as a Shareholder. A Participant shall not be entitled to any
of the rights or privileges of a shareholder of the Company with respect to
shares of Common Stock, including the right to vote or direct the voting or to
receive any dividends that may be declared by the Company, until (a) the
Participant actually has paid the purchase price for such shares and (b)
certificates for such shares have been issued either to the agent or to the
Participant, both as provided in Section 10.

         12. Rights Not Transferable. A Participant's rights under this Plan are
exercisable only by the Participant during his or her lifetime, and may not be
sold, pledged, assigned, transferred or disposed of in any manner other than by
will or the laws of descent and distribution. Any attempt to sell, pledge,
assign, transfer or dispose of the same shall be null and void and without
effect. The amounts credited to a Recordkeeping Account may not be sold,
pledged, assigned, transferred or disposed of in any way, and any attempted
sale, pledge, assignment, transfer or other disposition of such amounts will be
null and void and without effect.

         13. Administration of the Plan. This Plan shall be administered by the
Committee, which is authorized to make such uniform rules as may be necessary to
carry out its provisions. The Committee shall determine any questions arising in
the administration, interpretation and application of this Plan, and all such
determinations shall be conclusive and binding on all parties. If the Board of
Directors has not designated a committee to administer this Plan, then the
Compensation Committee of the Board of Directors shall constitute the Committee.

         14. Adjustment upon Changes in Capitalization. In the event of any
change in the Common Stock of the Company by reason of stock dividends, stock
splits, reverse stock splits, corporate separations, recapitalizations, mergers,
consolidations, combinations, exchanges of shares and the like, the aggregate
number and class of shares available under this Plan and the number, class and
purchase price of shares available but not yet purchased under this Plan, may be
adjusted appropriately by the Committee.

         15. Registration of Certificates. Stock certificates will be registered
in the name of the Participant, or jointly in the name of the Participant and
another person, as the Participant may direct on an appropriate form filed with
the Company or the agent.

         16. Amendment of Plan. The Board of Directors may at any time amend
this Plan in any respect which shall not adversely affect the rights of
Participants pursuant to shares previously acquired under the Plan, except that,
without shareholder approval, no amendment shall be made to (a) increase the
number of shares reserved under this Plan, or (b) change the designation of
corporations whose employees may be eligible to participate in the Plan.

         17. Effective Date of Plan. This Plan shall be effective upon approval
thereof by the shareholders of the Company. All rights of Participants in any
offering hereunder shall terminate at the earlier of (a) the day that
Participants become entitled to purchase a number of shares of Common Stock
equal to or greater than the number of shares remaining available for purchase
or (b) at any time, at the discretion of the Board of Directors. Except as
otherwise determined by the Board of Directors, upon termination of this Plan,
the Company shall pay to each Participant cash in an amount equal to the entire
balance in such Participant's Recordkeeping Account.


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         18. Governmental Regulations and Listing. All rights granted or to be
granted to Eligible Employees under this Plan are expressly subject to all
applicable laws and regulations and to the approval of all governmental
authorities required in connection with the authorization, issuance, sale or
transfer of the shares of Common Stock reserved for this Plan, including,
without limitation, there being a current registration statement of the Company
under the Securities Act of 1933, as amended, covering the shares of Common
Stock purchasable on the last day of the Purchase Period applicable to such
shares, and if such a registration statement shall not then be effective, the
term of such Purchase Period shall be extended until the first business day
after the effective date of such a registration statement, or post-effective
amendment thereto. If applicable, all such rights hereunder are also similarly
subject to effectiveness of an appropriate listing application to a national
market system covering the shares of Common Stock under the Plan upon official
notice of issuance.

         19. Miscellaneous.

                  19.1. This Plan shall not be deemed to constitute a contract
         of employment between the Company and any Participant, nor shall it
         interfere with the right of the Company to terminate any Participant
         and treat him or her without regard to the effect which such treatment
         might have upon him or her under this Plan.

                  19.2. Wherever appropriate as used herein, the masculine
         gender may be read as the feminine gender, the feminine gender may be
         read as the masculine gender, the singular may be read as the plural
         and the plural may be read as the singular.

                  19.3. This Plan, and all agreements hereunder, shall be
         construed in accordance with and governed by the laws of the State of
         Colorado.