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                                                                  Exhibit 4.10


                              SECOND AMENDMENT TO
                                 CHEMFIRST INC.
           401(k) SAVINGS AND EMPLOYEE STOCK OWNERSHIP PLAN AND TRUST

         THIS AMENDMENT, effective as specifically stated herein, by and
between CHEMFIRST INC., a Business Corporation, having its principal office in
Jackson, Mississippi (hereinafter referred to as "Employer"), and CHARLES
SCHWAB TRUST COMPANY (hereinafter sometimes referred to as "Trustee");

R E C I T A L S:

         A. WHEREAS, the Employer has previously established the ChemFirst Inc.
401(k) Savings and Employee Stock Ownership Plan and Trust ("Plan and Trust")
for the benefit of those employees who qualify thereunder and for their
beneficiaries; and

         B. WHEREAS, the Employer desires to amend the Plan and Trust to (i)
clarify the definition of Eligible Employee; (ii) increase the cashout
distribution threshold to $5,000; and (iii) incorporate those special trust
provisions requested by the Plan Trustee that are described in the Addendum &
Letter Agreement attached hereto, for informational purposes only, as Exhibit
A;

         NOW, THEREFORE, pursuant to Section 10.01 of the Plan and Trust, the
following amendment is hereby made and shall be effective as specifically
stated herein:

1.       EFFECTIVE JANUARY 1, 1999, SECTION 1.13 OF THE PLAN IS AMENDED AS
         UNDERLINED TO READ AS FOLLOWS:

1.13     Eligible Employee Classification

         An Eligible Employee Classification is a classification of Employees,
         the members of which are eligible to participate in the Plan. All
         Employees who are classified as "Regular Employees" are eligible to
         participate in the Plan. Any reference to Employee within this
         Agreement is assumed to mean an Employee who is classified as a
         Regular Employee.


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2.       EFFECTIVE JANUARY 1, 1997, SECTION 1.34(e) OF THE PLAN IS AMENDED AS
         UNDERLINED TO READ AS FOLLOWS:

1.34     Qualified Annuity Definitions

* * * *

         (e)      Qualified Survivor Annuity

                  A Qualified Survivor Annuity which a Surviving Spouse will be
                  eligible to receive under the provisions of Section 6.02
                  means a monthly benefit payable for the remaining lifetime of
                  the Surviving Spouse. The amount of the Qualified Survivor
                  Annuity benefit will be the amount of benefit which can be
                  purchased from an Insurer with the Participant's Vested
                  Accrued Benefit.

                  If the Participant's Vested Accrued Benefit is $3,500 ($5,000
                  for Plan Years beginning after August 5, 1997) or less, the
                  Plan Administrator will direct the immediate distribution of
                  the Participant's Vested Accrued Benefit to the Surviving
                  Spouse. If the Participant's Vested Accrued Benefit at the
                  time of any distribution exceeds $3,500 ($5,000 for Plan
                  Years beginning after August 5, 1997), the Vested Accrued
                  Benefit at any later time will be deemed to exceed $3,500
                  ($5,000 for Plan Years beginning after August 5, 1997). The
                  Surviving Spouse may elect to receive the Qualified Survivor
                  Annuity as a lump sum.

3.       EFFECTIVE JANUARY 1, 1997, SECTION 5.05 OF THE PLAN IS AMENDED AS
         UNDERLINED TO READ AS FOLLOWS:

5.05     Form of Benefit Payment
         Subject to the provisions of Section 5.06, the Plan Administrator will
         direct the Trustee to make the payment of any benefit provided under
         this Plan upon the event giving rise to such benefit within 60 days
         following the receipt of a Participant's written request for the
         payment of benefits on a form provided by the Plan Administrator. The
         Plan Administrator may temporarily suspend such processing in the
         event of unusual or extraordinary circumstances such as the conversion
         of Plan records from one recordkeeper to another.

         The form of benefit will be determined as follows:

         (a)      a Participant who is not married on the date benefits are to
                  commence will be provided a Qualified Life Annuity, unless a
                  lump sum payment is elected, under a Qualified Election, by
                  the Participant within the 90-day period which ends on his
                  benefit commencement date.

         (b)      a Participant who is married on the date benefits commence
                  will be provided a Qualified Joint and Survivor Annuity
                  unless a lump sum payment is elected, under a Qualified
                  Election, by the Participant within the 90-day period which
                  ends on his benefit commencement date.

         Within the 90-day period which ends on a married Participant's
         expected benefit commencement date, the Plan Administrator will
         provide each Participant with a written explanation of:

         (a)      the terms and conditions of a Qualified Joint and Survivor
                  Annuity;

         (b)      the Participant's right to make and the effect of a Qualified
                  Election to waive the Qualified Joint and Survivor Annuity
                  form of benefit;

         (c)      the rights of a Participant's spouse; and

         (d)      the right to make, and the effect of, a revocation of a
                  previous Qualified Election to waive the Qualified Joint and
                  Survivor Annuity.


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         Notwithstanding the above, if a terminated Participant's Vested
         Accrued Benefit is $3,500 ($5,000 for Plan Years beginning after
         August 5, 1997) or less, such Participant's Vested Accrued Benefit
         shall be payable in a lump sum of the entire amount of his Vested
         Accrued Benefit. If the value of his Vested Accrued Benefit at the
         time of any distribution exceeds $3,500 ($5,000 for Plan Years
         beginning after August 5, 1997), the value of his Vested Accrued
         Benefit at any later time will be deemed to also exceed $3,500 ($5,000
         for Plan Years beginning after August 5, 1997).

         Upon request, the Participant may receive his benefit paid in a series
         of substantially equal annual or more frequent installments from the
         Trust Fund over a period certain not extending beyond the end of the
         period measured by the joint life and last survivor expectancy of the
         Participant and his spouse. A Participant may elect to receive an
         installment distribution in the form of a Nontransferable Annuity
         Contract. The Plan Administrator and the Trustee will have the power
         to establish rules and guidelines as deemed necessary or appropriate
         with regard to the payment of benefits under the installment payment
         form.

         Notwithstanding the foregoing, if Company Stock acquired with the
         proceeds of an Acquisition Loan available for distribution consist of
         more than one class, a distributee must receive substantially the same
         proportion of each class. A Participant entitled to a distribution
         under this Section shall have the right to demand that all payments
         under the foregoing paragraphs be made in Company Stock or in cash for
         fractional shares to the extent his or her Accounts are invested in
         Company Stock. A Participant's benefits attributable to Company Stock
         may be paid in whole or in part in cash.

4.       EFFECTIVE JANUARY 1, 1997, SECTION 7.02(b) OF THE PLAN IS AMENDED BY
         ADDING THE FOLLOWING SUBSECTION TO READ AS FOLLOWS:

7.02     (b)      Where Employer Maintains a Qualified Defined Benefit Plan

* * * * *

                  (4)      For Plan Years beginning after December 31, 1999,
                           the combined plan limits of Code Section 415(e)
                           shall no longer apply.

5.       EFFECTIVE JANUARY 1, 1997, SECTION 7.03(a) OF THE PLAN IS AMENDED BY
         ADDING THE FOLLOWING PARAGRAPH TO READ AS FOLLOWS:

7.03     Definitions Applicable to Article 7

* * * * *

         Notwithstanding the foregoing, in the case of a Participant (i) who is
         permanently and totally disabled (as provided in Code Section
         415(c)(3)(C), (ii) who is not an eligible Highly Compensated Employee,
         and (iii) with respect to whom the Employer elects to have this
         paragraph apply, the term Aggregate Compensation for purposes of this
         section shall mean the Aggregate Compensation the Participant would
         have received for the Plan Year if the Participant had been paid at
         the rate of Aggregate Compensation paid immediately before becoming
         permanently and totally disabled. This subsection shall apply only if
         contributions made with respect to amounts treated as Aggregate
         Compensation under this paragraph are nonforfeitable when made.

6.       EFFECTIVE JANUARY 1, 1997, SECTION 7.03(j) OF THE PLAN IS AMENDED IN
         ITS ENTIRETY TO READ AS FOLLOWS:

7.03     Definitions Applicable to Article 7

* * * * *

(j)      Defined Contribution Limit


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         The Defined Contribution Limit for a given Limitation Year is equal to
         the lesser of (1) the Defined Contribution Compensation Limit, which
         is 25% of Aggregate Compensation applicable to the Limitation Year, or
         (2) the Defined Contribution Dollar Limit, which is $30,000. If a
         short Limitation Year is created because of an amendment changing the
         Limitation Year to a different 12 consecutive month period, the
         Defined Contribution Dollar Limit is multiplied by a fraction, the
         numerator of which is equal to the number of months in the short
         Limitation Year and the denominator of which is 12.

7.       EFFECTIVE JANUARY 1, 1997, ARTICLE 11 IS AMENDED BY ADDING SECTION
         11.17 TO READ AS FOLLOWS:

11.17    Special Rules Concerning Trustee Responsibilities

         Notwithstanding the foregoing sections of this Article 11, the
         following provisions regarding the investment of Plan assets and the
         Trustee's duties and responsibilities thereto shall override any Plan
         provision to the contrary:

         (a)      Investments.

                  1.       Notwithstanding the provisions of Section 11.04
                           above, except as provided below, the Plan
                           Administrator shall have all power over and
                           responsibility for the management, disposition, and
                           investment of the Trust assets, and the Trustee
                           shall comply with proper written directions of the
                           Plan Administrator concerning those assets. Except
                           to the extent required by ERISA, the Trustee shall
                           have no duty or responsibility to review, initiate
                           action, or make recommendations regarding Trust
                           assets and shall retain assets until directed in
                           writing by the Plan Administrator to dispose of
                           them.

                           A.       As permitted under the Plan, each
                                    Participant and/or beneficiary may have
                                    investment power over the account
                                    maintained for him or her, and may direct
                                    the investment and reinvestment of assets
                                    of the account among the options authorized
                                    by the Plan Administrator. The Trustee
                                    shall have no duty or responsibility to
                                    review or make recommendations regarding
                                    investments made at the direction of the
                                    Plan Administrator or Participant and shall
                                    be required to act only upon receipt of
                                    proper written directions.

                           B.       As permitted under the Plan, the Plan
                                    Administrator may appoint an investment
                                    manager or managers within the meaning of
                                    section 3(38) of ERISA to direct, control
                                    or manage the investment of all or a
                                    portion of the Trust assets, as provided in
                                    sections 3(38) and 403(a)(2) of ERISA.

                  2.       In its administration of the Trust Fund, the Trustee
                           shall have and exercise whatever powers are
                           necessary to discharge its obligations and exercise
                           its rights under the Trust Agreement. Subject to the
                           direction of the Plan Administrator, or the person
                           authorized to make investment decisions (the
                           "Authorized Person"), the Trustee shall have full
                           power and authority with respect to property held in
                           the Trust Fund to exercise all such rights and
                           privileges, including, without limitation, the
                           following:

                           A.       To deposit securities in a security
                                    depository and permit the securities so
                                    deposited to be held in the name of the
                                    depository's nominee, and to deposit
                                    securities issued or guaranteed by the U.S.
                                    Government or any agency or instrumentality
                                    thereof, including securities evidenced by
                                    book entry rather than by certificate, with
                                    the U.S. Department of the Treasury, a
                                    Federal Reserve Bank or other appropriate
                                    custodial entity, in the same account as
                                    the Trustee's own property, provided the
                                    Trustee's records and accounts show that
                                    such securities are assets of the Trust
                                    Fund;


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                           B.       To deliver to the Administrator, or the
                                    person or persons identified by the
                                    Administrator, proxies and powers of
                                    attorney and related informational
                                    material, for any shares or other property
                                    held including Employer Securities in the
                                    Trust. Subject to the provisions of Section
                                    11.17(a)(2)(C), the Administrator shall
                                    have responsibility for instructing the
                                    Trustee as to voting such shares and the
                                    tendering of such shares, by proxy or in
                                    person, except to the extent such
                                    responsibility is delegated to another
                                    person, under the terms of the Plan or
                                    Trust Agreement or under an agreement
                                    between the named fiduciary of the Plan and
                                    an investment manager, in which case such
                                    persons shall have such responsibility. The
                                    Trustee may use agents to effect such
                                    delivery to the Administrator or the person
                                    or persons identified by the Administrator.
                                    In no event shall the Trustee be
                                    responsible for the voting or tendering of
                                    shares of securities held in the Trust or
                                    for ascertaining or monitoring whether, or
                                    how, proxies are voted or whether the
                                    proper number of proxies is received.

                           C.       In addition to the provisions of Section
                                    12.01(e) of the Plan, all voting rights
                                    with respect to shares of Company Stock
                                    held in the Trust Fund and allocated to
                                    Participants' Accounts shall be exercised
                                    by the Trustee in such manner as may be
                                    directed by the respective Participant
                                    (which term, for purposes of this
                                    subsection C, shall include the beneficiary
                                    of a deceased Participant and any alternate
                                    payee for whom an account has been
                                    established with an interest in Company
                                    Stock). Any shares of Company Stock in the
                                    Trust Fund that are allocated to
                                    Participants who fail to give directions to
                                    the Trustee shall be voted by the Trustee
                                    in the same proportion as the Shares for
                                    which voting instructions have been
                                    received, subject to the power of the
                                    Administrator to direct the Trustee to vote
                                    such shares in a different manner, if the
                                    Administrator determines that such action
                                    is consistent with its fiduciary
                                    obligations under ERISA. The Administrator
                                    may establish such rules and guidelines as
                                    it deems necessary to properly effect the
                                    provisions of this section;

                           D.       In addition to the provisions of Section
                                    11.04(h) of the Plan, to register Trust
                                    Fund property in the Trustee's own name, in
                                    the name of a nominee or in bearer form,
                                    provided the Trustee's records and accounts
                                    show that such property is an asset of the
                                    Trust Fund;

         (b)      Settlement of Accounts. In addition to the provisions of
                  Section 11.08 of the Plan, the Trustee's account shall be
                  deemed approved upon receipt by the Trustee of the Employer's
                  written approval of the account or upon the passage of the
                  sixty day period of time after receipt by the Employer,
                  except for any matters covered by written objections that
                  have been delivered to the Trustee by the Employer and for
                  which the Trustee has not given an explanation or made an
                  adjustment satisfactory to the Employer.

         (c)      Company Stock. In addition to the provisions of Section 12.01
                  of the Plan:

                  1.       No assets of the Trust Fund shall be invested in the
                           securities of the Employer or its affiliates unless
                           the Administrator determines that the securities are
                           exempt from registration under the federal
                           Securities Act of 1933, as amended, and are exempt
                           from registration or qualification under the
                           applicable state law, and of any other applicable
                           blue sky law, or in the alternative, that the
                           securities have been so registered and/or qualified.
                           The Administrator shall also specify what
                           restrictive legend on transfer, if any, is required
                           to be set forth on the certificates for the
                           securities and the procedure to be followed by the
                           Trustee to effectuate a resale of such securities.
                           The Administrator shall not direct the investment in
                           "employer securities" or "employer real property",
                           within the meaning of section 407 of ERISA, if such
                           investment


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                           would be prohibited by ERISA. The Administrator
                           shall only direct the investment of Trust funds into
                           securities of the Employer or an affiliate (i) if
                           those securities are traded on an exchange
                           permitting a readily ascertainable fair market
                           value, or (ii) if the Administrator shall have
                           obtained a current valuation by a qualified
                           independent appraiser.

                  2.       The Employer represents and warrants that it will
                           take all responsibility (and hereby assumes all
                           liability for the failure) to notify Participants of
                           any limitations on investment directions necessary
                           or appropriate to comply with federal securities
                           laws (including the Exchange Act and the 1933 Act),
                           including but not limited to the frequency of
                           investment changes by certain officers and
                           shareholder-employees pursuant to Section 16(a) and
                           the volume of trading in Company Stock pursuant to
                           Rule l0b-6. Consequently the Trustee shall have no
                           liability to a Participant, and beneficiary, or the
                           Employer for carrying out instructions relating to
                           the acquisition or disposition of Company Stock
                           regardless of whether those instructions subject
                           such person or the Employer to any liability.

                           The Employer represents and warrants that either the
                           percentage of the issued and outstanding class of
                           equity security registered under section 12 of the
                           Exchange Act which is Company Stock owned by the
                           Plan (the "Plan Percentage") is less than 4.5% or
                           that the Plan and its prior trust have complied with
                           all notice and filing requirements imposed by
                           federal securities laws with regard to Company
                           Stock. The Employer covenants that it will (a)
                           notify the Trustee in writing within 5 business days
                           following any date as of which the Plan Percentage
                           equals or exceeds 4.5%, (b) monitor the Plan
                           Percentage on a daily basis so long as the Plan
                           Percentage is at least 4.5%, (c) notify the Trustee
                           in writing within 5 business days following any date
                           as of which the Plan Percentage equals or exceeds 5%
                           and, if applicable, 10%, and (d) provide monthly
                           written reports to the Trustee disclosing the Plan
                           Percentage. The foregoing monitoring and
                           notification requirements shall cease during any
                           month when the Plan Percentage is below 4.5% for
                           each day of the month. The provisions of this
                           Section shall survive the termination of this Trust
                           Agreement.

                  3.       The election to purchase stock from a participant as
                           described in Section 12.05 of the Plan and Trust,
                           shall be the exclusive right and option of the Plan
                           Administrator and the Trustee shall be responsible
                           only for following the directions of the Plan
                           Administrator.

         (d)      Resignation or Removal of Trustee. Notwithstanding the
                  provisions of Section 11.14, if either party has given notice
                  of Trustee removal or resignation as provided under Section
                  11.14 above, and upon the expiration of the advance notice
                  period no other successor Trustee has been appointed and has
                  accepted such appointment, this provision shall serve as (i)
                  notice of appointment of the Chief Executive Officer of the
                  Employer as Trustee and (ii) as acceptance by that person of
                  that appointment.

         (e)      Applicable Law. Notwithstanding the provisions of Section
                  8.04, the Trust will be administered in the State of
                  California, and its validity, construction, and all rights
                  hereunder shall be governed by ERISA and, to the extent not
                  preempted, by the laws of California. If any provision of
                  this Agreement shall be invalid or unenforceable, the
                  remaining provisions shall continue to be fully effective.



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         IN WITNESS WHEREOF, this instrument has been executed by the duly
authorized and empowered officer of the Employer, this 1st day of July, 1999.


                                       EMPLOYER:

                                       CHEMFIRST INC.



                                       By: /s/ William B. Kemp
                                           ------------------------------
                                               William B. Kemp
                                               Vice President

                                       TRUSTEE:

                                       CHARLES SCHWAB TRUST COMPANY


                                       By: /s/ K. Mason
                                           ------------------------------


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