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                                                                   Exhibit 10.24

                                 THIRD AMENDMENT
                                       TO
       THE ST. JOE COMPANY 1999 EMPLOYEE STOCK PURCHASE PLAN ("JOESHARE")

   This THIRD AMENDMENT (the "Amendment") to The St. Joe Company 1999
Employee Stock Purchase Plan (the "Plan") is made pursuant to Sections 4 and 15
thereof, and shall be effective January 1, 2003.

   1. EXCLUSION OF CERTAIN EMPLOYEES. Section 5 of the Plan shall be amended
      in its entirety to read as follows:

      "5. ELIGIBLE EMPLOYEES. Any employee of the Company, its Subsidiaries
          organized under the laws of any state in the United States, and any
          Subsidiary designated by the Compensation Committee which is
          organized under the laws of any jurisdiction outside of the United
          States, shall be eligible to participate in the Plan, except that
          the following classes shall be excluded:

            (a)   workers who are treated as independent contractors (regardless
                  of whether they are later determined by a court of law or
                  governmental authority to be common-law employees);

            (b)   leased employees;

            (c)   a director of the Company or of any Subsidiary who is not an
                  employee;

            (d)   workers whose customary employment is for not more than five
                  (5) months in any calendar year (seasonal or temporary
                  employees); and

            (e)   employees who have not been employed for at least ninety (90)
                  days.

      This Section 5 is subject to the provisions of Section 9."

   2. ELIMINATION OF QUARTERLY RE-ENTRY DATE. The second paragraph of Section 6
      of the Plan shall be amended in its entirety to read as follows:

      "A Participant may cease, re-start, increase or decrease that
      Participant's payroll deduction, at any time by filing a new Enrollment
      Form at least thirty (30) days prior to such change, in accordance with
      procedures adopted by the Compensation Committee. If an Enrollment Form is
      filed less than thirty (30) days prior to such change, the Company will
      accommodate such request as of the intended effective date if it
      determines in its sole discretion that it is administratively feasible to
      do so."

   3. EXCLUSION OF DRAWS. The following sentence shall be added to the end of
      Section 6:

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      "Any draw paid to a Participant on or after January 29, 2003, may not be
      used to purchase Common Stock under this Plan."

   4. DEFAULT BENEFICIARY. The last sentence of Section 14 of the Plan shall
      be replaced with the following:

      "If a named beneficiary does not survive the Participant, such
      beneficiary's share shall be delivered to the Participant's remaining
      named beneficiaries according to their percentages. If there are no
      surviving beneficiaries or the Participant has not designated a
      beneficiary under this Plan, the Participant's Investment Account shall be
      delivered the Participant's surviving spouse; or if there is no surviving
      eligible spouse, in equal shares to any surviving children of the
      Participant; or if neither of the above survive the Participant, to the
      Participant's estate."

Except as expressly modified by this Amendment, the terms, provisions, and
conditions of the Plan shall remain unchanged and are hereby ratified and
confirmed as being in full force and effect.

Executed as of this 31st day of December by the duly authorized officer of the
Company.

                                            THE ST. JOE COMPANY

                                            By: /s/ Rachelle Gottlieb
                                                -------------------------------
                                                Rachelle Gottlieb
                                                Vice President - Human Resources