Document:

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                                                                   Exhibit 4.1C

                  THIRD AMENDMENT TO AND SUPPLEMENTAL INDENTURE

                  THIS THIRD AMENDMENT TO AND SUPPLEMENTAL INDENTURE ("Third
Amendment") is made this 27th day of December, 2000, by and among Chattem, Inc.,
a Tennessee corporation (the "Company"), Signal Investment & Management Co., a
Delaware corporation (the "Guarantor") and SouthTrust Bank (the "Trustee"),
under the following circumstances:

                  A.       The Company has issued its 12 3/4% Senior
Subordinated Notes due 2004 in the original aggregate principal amount of
$75,000,000 (herein the "Notes").

                  B.       The Notes are secured by the Indenture dated
August 3, 1994 among the Company, the Guarantor and the Trustee
("Indenture"), which was amended by Supplemental Indentures dated May 23,
1995 and March 24, 1998.

                  C.       The Company and the Guarantor, having received the
written approval of the holders of at least a majority in interest in
principal amount of the Notes pursuant to Section 9.02 of the Indenture, and
the Trustee desire to amend the Indenture as provided hereinafter.

                  NOW, THEREFORE, in consideration of the premises and of the
mutual covenants and agreements contained in this Third Amendment, the parties
agree:

                  1.       Section 4.07 of the Indenture shall be deleted in
its entirety and in lieu thereof shall be inserted the following:

                           Section 4.07. LIMITATION ON RESTRICTED PAYMENTS. The
         Company will not, and will not permit any of its Subsidiaries to,
         directly or indirectly: (i) declare or pay any dividend or make any
         Distribution on account of the Company's or any of its Subsidiaries'
         Equity Interests (other than dividends or Distributions payable in
         Equity Interests (other than Disqualified Stock of the Company or
         dividends or Distributions payable to the Company or, in the case of a
         Subsidiary, from such Subsidiary to any Wholly Owned Subsidiary of the
         Company that is a Guarantor); (ii) purchase, redeem or otherwise
         acquire or retire for value any Equity Interests of the Company or any

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         Subsidiary or other Affiliate of the Company (other than any such
         Equity Interests owned by the Company or any Wholly Owned Subsidiary of
         the Company that is a Guarantor); (iii) purchase, redeem or otherwise
         acquire or retire for value any Indebtedness that is pari passu with or
         subordinated to the Securities (other than the Securities or the 1998
         Notes (as hereinafter defined) (including pursuant to the 1998 Notes
         Offer (as hereinafter defined)); (iv) redeem, repurchase or defease
         (including, without limitation, in substance or legal defeasance) or in
         any other manner acquire or retire for value by the Company or any
         Subsidiary of any Junior Debt or debt ranking pari passu with the
         Securities prior to any scheduled maturity, scheduled repayment or
         scheduled sinking fund payment; or (v) make any Restricted Investment
         (all such payments and other actions set forth in clauses (i) through
         (iv) above plus the net amount of Restricted Investment being
         collectively referred to as "Restricted Payments"), unless, at the time
         of such Restricted Payment:

                           (a)   no Default or Event of Default shall have
                  occurred and be continuing or would occur as a consequence
                  thereof;

                           (b)   the Company would, at the time of such
                  Restricted Payment and after giving pro forma effect
                  thereto as if such Restricted Payment had been made at the
                  beginning of the applicable four-quarter period immediately
                  preceding such Restricted Payment, have been permitted to
                  incur at least $1.00 of additional Indebtedness pursuant to
                  the Fixed Charge Coverage Ratio test set forth in the first
                  paragraph of Section 4.09 hereof; and

                           (c)   such Restricted Payment, together with the
                  aggregate of all other Restricted Payments made by the Company
                  and its Subsidiaries after the date of this Indenture
                  (including Restricted Payments permitted by clause (i) of the
                  next succeeding paragraph), is less than the sum of (x) 50% of
                  the Consolidated Net Income of the Company for the period
                  (taken as one accounting period) from the date of this
                  Indenture to the

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                  end of the Company's most recently ended fiscal quarter
                  (or, if such Consolidated Net Income for such period is a
                  deficit, minus, 100% of such deficit, plus (y) 100% of the
                  aggregate net cash proceeds received by the Company from
                  the issue or sale of Equity Interests of the Company or any
                  security convertible or exchangeable for any such Equity
                  Interests that has been so converted or exchanged (other
                  than Equity Interests or other securities sold to a
                  Subsidiary of the Company and other than Disqualified
                  Stock).

                           The foregoing provisions shall not prohibit (i) up to
         an aggregate of $1.0 million of additional Restricted Payments since
         the Issuance Date; (ii) the payment of any dividend within 60 days
         after the date of declaration thereof, if at said date of declaration
         such payment would have complied with the provisions of this Indenture;
         (iii) the redemption, repurchase, retirement or other acquisition of
         any Equity Interests of the Company in exchange for, or out of the
         proceeds of, the substantially concurrent sale (other than to a
         Subsidiary of the Company that is a Guarantor) of other Equity
         Interests of the Company (other than any Disqualified Stock) or (iv)
         the Company from redeeming Junior Debt with the proceeds from the
         issuance of Junior Debt, so long as such Junior Debt has a Weighted
         Average Life to Maturity greater than the remaining Weighted Average
         Life to Maturity to the Junior Debt so redeemed; provided, however,
         that except in the case of clause (ii), no Default or Event of Default
         shall have occurred or be continuing or would occur as a consequence
         thereof.

                           Not later than 10 days prior to making any Restricted
         Payment, the Company shall deliver to the Trustee an Officers'
         Certificate stating that such Restricted Payment is permitted and
         setting forth the basis upon which the calculations required by the
         covenant "Limitation on Restricted Payments" were computed, which
         calculations may be based upon the Company's latest available financial
         statements.

                           For purposes of this Indenture, the "1998 Notes"
         means the Company's outstanding 8 7/8% Senior Subordinated Notes due
         2008 which were originally

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         issued in 1998, and the "1998 Notes Offer" means the Company's offer
         to purchase for cash $75.3 million of the 1998 Notes, pursuant to
         the Offer to Purchase and Consent Solicitation Statement dated
         December 11, 2000, as such offer to purchase may be amended by the
         Company.

                  2.       The amendment to the Indenture set forth in
Section 1 above shall not become operative unless and until the Notes are
accepted for purchase by the Company pursuant to the Offer to Purchase and
Consent Solicitation Statement dated December 11, 2000.

                  3.       Except as expressly set forth herein, this Third
Amendment shall not supersede or otherwise modify the terms and conditions of
the Indenture.

                          [Signature Page Follows]

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                  IN WITNESS WHEREOF, this Third Amendment to and Supplemental
Indenture has been executed by a duly authorized officer of the Company, the
Guarantor and the Trustee.

Dated as of December 27, 2000.

ATTEST:                                     CHATTEM, INC.

By:                                         By:
   -----------------------------               --------------------------------
   Secretary                                   A. Alexander Taylor, II
                                               President

Dated as of December 27, 2000.

ATTEST:                                     SIGNAL INVESTMENT & MANAGEMENT
                                            CO., a Guarantor

By:                                         By:
   -----------------------------               --------------------------------
   Secretary                                   A. Alexander Taylor, II
                                               President

Dated as of December 27, 2000.

ATTEST:                                     SOUTHTRUST BANK

By:                                         By:
   -----------------------------               --------------------------------
                                               Name:  Judy Seier
                                               Title:  Vice President

                                       5<PAGE>

                                                                     EXHIBIT 4.2

                  FIRST AMENDMENT TO AND SUPPLEMENTAL INDENTURE

               THIS FIRST AMENDMENT TO AND SUPPLEMENTAL INDENTURE ("First
Amendment") is made this 3rd day of January, 2001, by and among Chattem, Inc., a
Tennessee corporation (the "Company"), Signal Investment & Management Co., a
Delaware corporation (the "Guarantor") and SouthTrust Bank (the "Trustee"),
under the following circumstances:

               A.  The Company has issued its 8 7/8% Senior Subordinated Notes
due 2008 in the original aggregate principal amount of $275,000,000 (herein the
"Notes").

               B.  The Notes are secured by the Indenture dated March 24, 1998
among the Company, the Guarantor and the Trustee ("Indenture").

               C.  The Company and the Guarantor, having received the written
approval of the holders of at least a majority in interest in principal amount
of the Notes pursuant to Section 9.02 of the Indenture, and the Trustee desire
to amend the Indenture as provided hereinafter.

               NOW, THEREFORE, in consideration of the premises and of the
mutual covenants and agreements contained in this First Amendment, the parties
agree:

               1.  The definition of "Fixed Charge Coverage Ratio" in Section
1.01 of the Indenture shall be deleted in its entirety and in lieu thereof shall
be inserted the following:

                   "Fixed Charge Coverage Ratio" means with respect to
                   any Person for any period, the ratio of the
                   Consolidated Cash Flow of such Person and its
                   Restricted Subsidiaries for such period to the Fixed
                   Charges of such Person and its Restricted
                   Subsidiaries for such period. In the event that the
                   referent Person or any of its restricted Subsidiaries
                   incurs, assumes, Guarantees or redeems any
                   Indebtedness (other than revolving credit borrowings)
                   or issues or redeems preferred stock subsequent to the

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                   commencement of the period for which the Fixed
                   Charge Coverage Ratio is being calculated but prior
                   to the date on which the event for which the
                   calculation of the Fixed Charge Coverage Ratio is
                   made (the "Calculation Date"), then the Fixed Charge
                   Coverage Ratio shall be calculated giving pro forma
                   effect to such incurrence, assumption, Guarantee or
                   redemption of Indebtedness, or such issuance or
                   redemption of preferred stock, as if the same had
                   occurred at the beginning of the applicable
                   four-quarter reference period. In addition, for
                   purposes of making the computation referred to above,
                   (i) acquisitions that have been made by the Company
                   or any of its Restricted Subsidiaries, including
                   through mergers or consolidations and including any
                   related financing transactions, during the
                   four-quarter reference period or subsequent to such
                   reference period and on or prior to the Calculation
                   Date shall be deemed to have occurred on the first
                   day of the four-quarter reference period and
                   Consolidated Cash Flow for such reference period
                   shall be calculated without giving effect to clause
                   (iii) of the proviso set forth in the definition of
                   Consolidated Net Income, and (ii) the Consolidated
                   Cash Flow attributable to discontinued operations, as
                   determined in accordance with GAAP, and operations or
                   businesses disposed of prior to the Calculation Date,
                   shall be excluded, and (iii) the Consolidated Cash
                   Flow attributable only to the Company's DEXATRIM-Registered
                   Trademark- products containing phenylpropanolamine shall
                   be excluded, and (iv) the Fixed Charges attributable to
                   discontinued operations, as determined in accordance
                   with GAAP, and operations or businesses disposed of
                   prior to the Calculation

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                   Date, shall be excluded, but only to the extent
                   that the obligations giving rise to such Fixed
                   Charges shall not be obligations of the referent
                   Person or any of its Restricted Subsidiaries
                   following the Calculation Date.

               2.  Section 4.07 of the Indenture shall be deleted in its
entirety and in lieu thereof shall be inserted the following:

                         Section 4.07. RESTRICTED PAYMENTS. The Company
               shall not, and shall not permit any of its Restricted
               Subsidiaries to, directly or indirectly: (i) declare or pay
               any dividend or make any other payment or distribution on
               account of the Company's or any of its Restricted
               Subsidiaries' Equity Interests (including, without limitation,
               any payment in connection with any merger or consolidation
               involving the Company or any of its Restricted Subsidiaries)
               or to the direct or indirect holders of the Company's or any
               of its Restricted Subsidiaries' Equity Interests in their
               capacity as such (other than dividends or distributions
               payable in Equity Interests (other than Disqualified Stock) of
               the Company or dividends or other distributions payable to the
               Company or a Restricted Subsidiary of the Company); (ii)
               purchase, redeem or otherwise acquire or retire for value
               (including, without limitation, in connection with any merger
               or consolidation involving the Company) any Equity Interests
               of the Company or any direct or indirect parent of the Company
               or other Affiliate of the Company (other than any such Equity
               Interests owned by the Company or any Wholly Owned Restricted
               Subsidiary of the Company); (iii) make any payment on or with
               respect to, or purchase, redeem, defease or otherwise acquire
               or retire for value any Indebtedness that is pari passu with
               or subordinated to the Notes (other than Notes or the 1994
               Notes (as hereinafter defined)

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               (including pursuant to the 1994 Notes Offer (as hereinafter
               defined)), except a payment of interest or principal at
               Stated Maturity; or (iv) make any Restricted Investment
               (all such payments and other actions set forth in clauses
               (i) through (iv) above being collectively referred to as
               "Restricted Payments"), unless, at the time of and after
               giving effect to such Restricted Payment:

                             (a) no Default or Event of Default shall have
                       occurred and be continuing or would occur as a
                       consequence thereof;

                             (b) the Company would, at the time of such
                       Restricted Payment and after giving pro forma effect
                       thereto as if such Restricted Payment had been made
                       at the beginning of the applicable four-quarter
                       period, have been permitted to incur at least $1.00
                       of additional Indebtedness pursuant to the Fixed
                       Charge Coverage Ratio test set forth in Section 4.09;
                       and

                             (c) such Restricted Payment, together with the
                       aggregate amount of all other Restricted Payments
                       made by the Company and its Restricted Subsidiaries
                       after the date of this Indenture (excluding Restricted
                       Payments permitted by clauses (ii), (iii) and (iv) of
                       the next succeeding paragraph), is less than the sum,
                       without duplication, of (i) 50% of the Consolidated Net
                       Income of the Company for the period (taken as one
                       accounting period) from the beginning of the first
                       fiscal quarter commencing after the date of this
                       Indenture to the end of the Company's most recently
                       ended fiscal quarter for which internal financial
                       statements are available at the time of such Restricted
                       Payment (or, if such Consolidated Net Income

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                       for such period is a deficit, less 100% of such deficit)
                       plus (ii) 100% of the aggregate net cash proceeds
                       received by the Company since the date of this Indenture
                       as a contribution to its common equity capital or from
                       the issue or sale of Equity Interests of the Company
                       (other than Disqualified Stock) or from the issue or sale
                       of Disqualified Stock or debt securities of the Company
                       that have been converted into such Equity Interests
                       (other than Equity Interests (or Disqualified Stock or
                       convertible debt securities) sold to a Subsidiary of
                       the Company), plus (iii) to the extent that any
                       Restricted Investment that was made after the date of
                       this Indenture is sold for cash or otherwise liquidated
                       or repaid for cash, the lesser of (A) the cash return of
                       capital with respect to such Restricted Investment (less
                       the cost of disposition, if any) and (B) the initial
                       amount of such Restricted Investment plus (iv) $7.5
                       million.

                             The foregoing provisions shall not prohibit
               (i) the payment of any dividend within 60 days after the date
               of declaration thereof, if at said date of declaration such
               payment would have complied with the provisions of this
               Indenture; (ii) the redemption, repurchase, retirement,
               defeasance or other acquisition of any pari passu or
               subordinated Indebtedness or Equity Interests of the Company
               in exchange for, or out of the net cash proceeds of the
               substantially concurrent sale (other than to a Restricted
               Subsidiary of the Company) of, other Equity Interests of the
               Company (other than any Disqualified Stock); provided that the
               amount of any such net cash proceeds that are utilized for any
               such redemption, repurchase, retirement, defeasance or other
               acquisition shall be excluded from clause (c)(ii) of the
               preceding paragraph; (iii)

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               the defeasance, redemption, repurchase or other acquisition of
               pari passu or subordinated Indebtedness with the net cash
               proceeds from an incurrence of Permitted Refinancing
               Indebtedness; (iv) the payment of any dividend by a Restricted
               Subsidiary of the Company to the holders of its common Equity
               Interests on a pro rata basis; and (v) the repurchase,
               redemption or other acquisition or retirement for value of any
               Equity Interests of the Company or any Restricted Subsidiary
               of the Company held by any member of the Company's (or any of
               its Restricted Subsidiaries') management pursuant to any
               management equity subscription agreement or stock option
               agreement; provided that the aggregate price paid for all such
               repurchased, redeemed, acquired or retired Equity Interests
               shall not exceed $500,000 in any twelve-month period and no
               Default or Event of Default shall have occurred and be
               continuing immediately after such transaction.

                             The Board of Directors may designate any
               Restricted Subsidiary to be an Unrestricted Subsidiary if such
               designation would not cause a Default. For purposes of making
               such determination, all outstanding Investments by the Company
               and its Restricted Subsidiaries (except to the extent repaid
               in cash) in the Subsidiary so designated shall be deemed to be
               Restricted Payments at the time of such designation and shall
               reduce the amount available for Restricted Payments under the
               first paragraph of this covenant. All such outstanding
               Investments shall be deemed to constitute Investments in an
               amount equal to the fair market value of such Investments at
               the time of such designation. Such designation shall only be
               permitted if such Restricted Payment would be permitted at
               such time and if such Restricted Subsidiary otherwise meets
               the definition of an Unrestricted Subsidiary.

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                             The amount of all Restricted Payments (other
               than cash) shall be the fair market value on the date of the
               Restricted Payment of the asset(s) or securities proposed to
               be transferred or issued by the Company or such Restricted
               Subsidiary, as the case may be, pursuant to the Restricted
               Payment. The fair market value of any non-cash Restricted
               Payment shall be determined by the Board of Directors whose
               resolution with respect thereto shall be delivered to the
               Trustee, such determination to be based upon an opinion or
               appraisal issued by an accounting, appraisal or investment
               banking firm of national standing if such fair market value
               exceeds $10.0 million. Not later than the date of making any
               Restricted Payment, the Company shall deliver to the Trustee
               an Officers' Certificate stating that such Restricted Payment
               is permitted and setting forth the basis upon which the
               calculations required by this Section 4.07 were computed,
               together with a copy of any fairness opinion required by this
               Indenture.

                             For purposes of this Indenture, the "1994
               Notes" means the Company's outstanding 12 3/4% Senior
               Subordinated Notes due 2004 which were originally issued in
               1994, and the "1994 Notes Offer" means the Company's offer to
               purchase for cash $7.9 million of the 1994 Notes, pursuant to
               the Offer to Purchase and Consent Solicitation Statement dated
               December 11, 2000, as such offer to purchase may be amended by
               the Company.

               3.  Section 4.10 of the Indenture shall be deleted in its
entirety and in lieu thereof shall be inserted the following:

                             Section 4.10 ASSET SALES. The Company shall
               not, and shall not permit any of its Restricted Subsidiaries
               to, consummate an Asset Sale unless (i) the Company (or the
               Restricted Subsidiary, as the case may be) receives
               consideration at

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               the time of such Asset Sale at least equal to the fair market
               value (evidenced by a resolution of the Board of Directors set
               forth in an Officers' Certificate delivered to the Trustee) of
               the assets or Equity Interests issued or sold or otherwise
               disposed of and (ii) at least 75% of the consideration
               therefor received by the Company or such Restricted Subsidiary
               is in the form of cash or Qualified Proceeds, provided, that
               the aggregate fair market value of Qualified Proceeds which
               may be received in consideration for Asset Sales pursuant to
               this clause (ii) shall not exceed $5.0 million since the Issue
               Date; provided, further that the amount of (x) any liabilities
               (as shown on the Company's or such Restricted Subsidiary's
               most recent balance sheet), of the Company or any Restricted
               Subsidiary (other than contingent liabilities and liabilities
               that are by their terms subordinated to the Notes or any
               guarantee thereof) that are assumed by the transferee of any
               such assets pursuant to a customary novation agreement that
               releases the Company or such Restricted Subsidiary from
               further liability and (y) any securities, notes or other
               obligations received by the Company or any such Restricted
               Subsidiary from such transferee that are contemporaneously
               (subject to ordinary settlement periods) converted by the
               Company or such Restricted Subsidiary into cash (to the extent
               of the cash received), shall be deemed to be cash for purposes
               of this provision.

                             Within 365 days after the receipt of any Net
               Proceeds from an Asset Sale, the Company may apply such Net
               Proceeds, at its option, (a) to permanently repay (and reduce
               the commitments under) Senior Indebtedness of the Company or a
               Guarantor or (b) to the acquisition of a Permitted Business,
               or a majority of the Voting Stock of, a Permitted Business,
               the making of a capital

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               expenditure or the acquisition of other long-term assets that
               are used or useful in a Permitted Business. Pending the final
               application of any such Net Proceeds, the Company may
               temporarily reduce revolving credit borrowings or otherwise
               invest such Net Proceeds in any manner that is not prohibited
               by this Indenture. Any Net Proceeds from Asset Sales that are
               not applied or invested as provided in the first sentence of
               this paragraph, other than Available BAN Net Proceeds (as
               hereinafter defined), shall be deemed to constitute "Excess
               Proceeds." When the aggregate amount of Excess Proceeds
               exceeds $5.0 million, the Company shall be required to make an
               offer to all Holders of Notes and all holders of other
               Indebtedness containing provisions similar to those set forth
               in this Indenture with respect to offers to purchase or redeem
               with the proceeds of sales of assets (an "Asset Sale Offer")
               to purchase the maximum principal amount of Notes and such
               other Indebtedness that may be purchased out of the Excess
               Proceeds, at an offer price in cash in an amount equal to 100%
               of the principal amount thereof plus accrued and unpaid
               interest and Liquidated Damages thereon, if any, to the date
               of purchase, in accordance with the procedures set forth in
               this Indenture and such other Indebtedness. To the extent that
               any Excess Proceeds remain after consummation of an Asset Sale
               Offer, the Company may use such Excess Proceeds for any
               purpose not otherwise prohibited by this Indenture. If the
               aggregate principal amount of Notes and such other Indebtedness
               tendered into such Asset Sale Offer surrendered by Holders
               thereof exceeds the amount of Excess Proceeds, the Trustee
               shall select the Notes and such other Indebtedness to be
               purchased on a pro rata basis. Upon completion of such offer
               to purchase, the amount of Excess Proceeds shall be reset at
               zero.

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                             For purposes of this Indenture, "BAN Sale"
               means the Company's sale of the BAN line of deodorant and
               anti-perspirant products to The Andrew Jergens Company, a
               wholly-owned subsidiary of Kao Corporation, on September 15,
               2000 for a purchase price of $160 million cash plus the right
               to receive up to an additional $6.5 million in future payments
               based upon levels of BAN sales in 2001 and 2002, and
               "Available BAN Net Proceeds" means the Net Proceeds from the
               BAN Sale remaining after the repayment of the Senior Credit
               Facility.

               4.  The amendments to the Indenture set forth in Sections 1, 2
and 3 above shall not become operative unless and until the Notes are accepted
for purchase by the Company pursuant to the Offer to Purchase and Consent
Solicitation Statement dated December 11, 2000, as amended.

               5.  Except as expressly set forth herein, this First Amendment
shall not supersede or otherwise modify the terms and conditions of the
Indenture.

                             [Signature Page Follows]

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               IN WITNESS WHEREOF, this First Amendment to and Supplemental
Indenture has been executed by a duly authorized officer of the Company, the
Guarantor and the Trustee.

Dated as of January 3, 2001.

ATTEST:                                    CHATTEM, INC.

By:                                        By:
   ---------------------------                ---------------------------------
   Secretary                                  A. Alexander Taylor, II
                                              President

Dated as of January 3, 2001.

ATTEST:                                    SIGNAL INVESTMENT & MANAGEMENT
                                           CO., a Guarantor

By:                                        By:
   ---------------------------                ---------------------------------
   Secretary                                  A. Alexander Taylor, II
                                              President

Dated as of January 3, 2001.

ATTEST:                                    SOUTHTRUST BANK

By:                                        By:
   ---------------------------                ---------------------------------
                                              Name:  Judy Seier
                                              Title:  Vice President

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