<PAGE>

                                                                     EXHIBIT 4.1

                      SECOND AMENDMENT TO CREDIT AGREEMENT

         THIS SECOND AMENDMENT TO CREDIT AGREEMENT dated as of July 26, 2001
(the "Amendment") by and among ROCK-TENN COMPANY, a Georgia corporation (the
"Borrower"), SUNTRUST BANK, a banking corporation organized under the laws of
the State of Georgia ("SunTrust"), the other banks and financial institutions
listed on the signature pages hereof, (SunTrust, and such other banks, lending
institutions, and assignees referred to collectively herein as the "Lenders"),
SUNTRUST BANK, in its capacity as Agent for the Lenders (the "Agent"), BANK OF
AMERICA, N.A., as Syndication Agent (the "Syndication Agent") and WACHOVIA BANK,
N.A., as Documentation Agent (the "Documentation Agent").

         WHEREAS, the Borrower, the Agent and the Lenders are parties to that
certain Credit Agreement dated as of June 30, 2000, by and among the Borrower,
the Agent and the other Lenders (as amended, the "Credit Agreement"; all
capitalized terms not otherwise defined herein shall have the meanings set forth
in the Credit Agreement), pursuant to which the Lenders have made available
certain financial accommodations to the Borrower;

         WHEREAS, the parties wish to amend the Credit Agreement on the terms
and conditions contained herein.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged by the parties hereto, the parties
hereto agree as follows:

          Section 1.       Amendments.

         (a)      The Credit Agreement is hereby amended by adding the following
new definition of "Acquired EBITDA" to Section 1.1 in its appropriate
alphabetical place:

                           "Acquired EBITDA" shall mean, with respect to any
                  Person, property, business or asset (any of the foregoing, a
                  "Pro Forma Entity") acquired pursuant to a Permitted
                  Acquisition for any period, the sum of the amounts for such
                  period of (a) the net income (or net loss) of such Pro Forma
                  Entity as defined according to GAAP minus the gain or loss
                  (net of any tax effect) resulting from the sale of any Capital
                  Assets by such Pro Forma Entity other than in the ordinary
                  course of business minus other extraordinary items, as defined
                  by GAAP plus (b) the aggregate amount deducted in determining
                  such net income (loss) in respect of (i) interest expense,
                  (ii) income taxes, and (iii) depreciation and amortization
                  expense, all as determined on a consolidated basis for such
                  Pro Forma Entity in accordance with GAAP.

         (b)      The Credit Agreement is hereby amended by deleting the
definition of "EBITDA" from Section 1.1 and substituting in lieu thereof the
following new definition of "EBITDA":

                           "`EBITDA' shall mean for any fiscal period,
                  Consolidated Net Income (or Consolidated Net Loss, as the case
                  may be) for such period plus (a) the aggregate amount deducted
                  in determining such Consolidated Net Income (Loss) in respect
                  of (i) Interest Expense, (ii) Income Taxes of the Consolidated
                  Companies determined in accordance with GAAP, (iii)
                  depreciation and amortization expense of the Consolidated
                  Companies determined in accordance with GAAP, in each case for
                  the applicable fiscal period, (iv) the amount of any non-cash
                  charges relating to plant shut-downs and asset impairment
                  charges actually taken by the Borrower for the quarter ending
                  March 31, 2000, (v) any non-cash charges actually taken by the
                  Consolidated Companies after March 31, 2000 which are
                  associated with the accelerated write-off of any tangible or
                  intangible assets related to the acquisition of Waldorf
                  Corporation provided such amounts do not exceed $100,000,000
                  in the aggregate through the Maturity Date, (vi) any non-cash
                  charges actually taken which are associated with the
                  accelerated write-off of any tangible or intangible assets
                  provided such amounts do not exceed $50,000,000 in the
                  aggregate through the Maturity Date and (vii) the amount of
                  cash charges actually taken which


<PAGE>

                  resulted from the Home Office and Folding Carton Division
                  reorganizations and the closing of the Borrower's Downingtown,
                  Pennsylvania converting facility, Norcross, Georgia folding
                  facility, Lynchburg, Virginia converting facility, Augusta,
                  Georgia folding facility, Madison, Wisconsin folding facility,
                  and Chicago, Illinois folding facility in an aggregate amount
                  not to exceed $4,832,000 for the fiscal quarter ending June
                  30, 2000, $5,637,000 for the fiscal quarter ending September
                  30, 2000, $1,906,000 for the fiscal quarter ending December
                  31, 2000 and an aggregate of $7,000,000 thereafter; in each
                  case for the Consolidated Companies determined on a
                  consolidated basis in accordance with GAAP, (b) actual rental
                  expense associated with any Synthetic Lease and (c) cash
                  distributions of earnings of Unrestricted Subsidiaries made to
                  a Consolidated Company to the extent previously excluded in
                  the determination of Consolidated Net Income or Consolidated
                  Net Loss by virtue of clause (i) of the respective definitions
                  thereof. For purposes of determining EBITDA hereunder, there
                  shall be included in such determination of EBITDA for any
                  period the Acquired EBITDA of any Person, property, business
                  or asset (other than an Unrestricted Subsidiary) acquired by a
                  Consolidated Company pursuant to a Permitted Acquisition and
                  not subsequently sold, transferred or otherwise disposed of by
                  any Consolidated Company during such period based on the
                  actual Acquired EBITDA of such Person, property, business or
                  asset for such period (including the portion thereof occurring
                  prior to such acquisition)."

         (c)      The Credit Agreement is hereby amended by deleting the
definition of "Indebtedness" from Section 1.1 and substituting in lieu thereof
the following new definition of "Indebtedness":

                           "`Indebtedness' of any Person shall mean, without
                  duplication, such Person's (i) Indebtedness for Borrowed
                  Money, (ii) obligations representing the deferred purchase
                  price of property or services (other than accounts payable
                  arising in the ordinary course of such Person's business),
                  (iii) obligations, whether or not assumed, secured by liens or
                  payable out of the proceeds or production from property or
                  assets now or hereafter owned or acquired by such Person, (iv)
                  Capital Lease Obligations, (v) any Guaranty, letter of credit
                  reimbursement obligations (without duplication of any of the
                  underlying obligations which otherwise constitutes
                  Indebtedness), and other contingent obligations in respect of
                  repayment of other types of Indebtedness, (vi) any off-balance
                  sheet liability retained by such Person in connection with
                  asset securitization programs and Synthetic Leases provided
                  that with respect to any Synthetic Lease, only the principal
                  obligations under such Synthetic Lease for which any
                  Consolidated Company has recourse liability shall constitute
                  Indebtedness, and (vii) any obligation under any foreign
                  exchange agreement. Notwithstanding the foregoing,
                  Indebtedness shall exclude all obligations, contingent or
                  otherwise, provided for in Statement of Financial Accounting
                  Standards No. 133, as in effect from time to time ("FASB
                  133"), other than obligations provided for in FASB 133 which
                  relate to clause (vii) of the definition of Indebtedness."

         (d)      The Credit Agreement is hereby amended by deleting Section
8.1(i) in its entirety and substituting in lieu thereof the following new
Section 8.1(i):

         (i)      Fixed Charges. Suffer or permit the ratio of (a) Consolidated
                  EBITR to (b) Fixed Charges as of the last day of each fiscal
                  quarter ending during the periods set forth below as
                  calculated for a period consisting of the four preceding
                  fiscal quarters, to be less than the ratio set forth opposite
                  such period:


                                      -2-
<PAGE>

<TABLE>
<CAPTION>
             PERIOD                             RATIO
-------------------------------------------------------------------
<S>                                           <C>
Closing Date through September                1.75:1.0
30, 2001
-------------------------------------------------------------------
October 1, 2001 through the                   2.00:1.0
Maturity Date
-------------------------------------------------------------------
</TABLE>


         (e)      The Credit Agreement is hereby amended by deleting Section
8.1(ii) in its entirety and substituting in lieu thereof the following new
Section 8.1(ii):

         (ii)     Total Funded Debt to EBITDA. Permit the ratio of (a) Total
                  Funded Debt to (b) EBITDA as of the last day of each fiscal
                  quarter ending during the periods set forth below as
                  calculated for a period consisting of the four preceding
                  fiscal quarters, to exceed the ratio set forth opposite such
                  period:

<TABLE>
<CAPTION>
             PERIOD                             RATIO
-------------------------------------------------------------------
<S>                                            <C>
Closing Date through September                 3.75:1.0
30, 2001
-------------------------------------------------------------------
October 1, 2001 through the                    3.50:1.0
Maturity Date
-------------------------------------------------------------------
</TABLE>

         (f)      The Credit Agreement is hereby amended by deleting Section
8.12 in its entirety and substituting in lieu thereof the following new Section
8.12:

                  SECTION 8.12. RESTRICTIVE AGREEMENTS.

                           Neither the Borrower nor any Restricted Subsidiary
                  shall, directly or indirectly, enter into, incur or permit to
                  exist any agreement that prohibits, restricts or imposes any
                  condition upon (a) the ability of the Borrower or any
                  Restricted Subsidiary to create, incur or permit any Lien upon
                  any of its assets or properties, whether now owned or
                  hereafter acquired, or (b) the ability of any Restricted
                  Subsidiary to pay dividends or other distributions with
                  respect to its common stock, to make or repay loans or
                  advances to the Borrower or any other Restricted Subsidiary,
                  to Guaranty Indebtedness of the Borrower or any other
                  Restricted Subsidiary or to transfer any of its property or
                  assets to the Borrower or any Restricted Subsidiary; provided,
                  that (i) the foregoing shall not apply to restrictions or
                  conditions imposed by law or by this Agreement or any other
                  Credit Document, (ii) the foregoing shall not apply to
                  customary restrictions and conditions contained in agreements
                  relating to the sale of a Restricted Subsidiary pending such
                  sale, provided such restrictions and conditions apply only to
                  the Restricted Subsidiary that is sold and such sale is
                  permitted hereunder, (iii) clause (a) shall not apply to
                  restrictions or conditions imposed by any agreement relating
                  to Purchase Money Indebtedness permitted by this Agreement if
                  such restrictions and conditions apply only to the property or
                  assets securing such Indebtedness, (iv) clause (a) shall not
                  apply to customary provisions in leases restricting the
                  assignment thereof and (v) clause (a) shall not apply to
                  restrictions or conditions imposed by that certain Indenture
                  dated July 31, 1995 between Rock-Tenn Company and SunTrust
                  Bank, N.A. (as successor trustee to Trust Company Bank),
                  provided that the aggregate amount of notes issued thereunder
                  does not exceed $500,000,000.


                                      -3-
<PAGE>

         Section 2.        Reduction of Revolving Credit Commitment.

         Notwithstanding any other provision contained in this Amendment, the
amendments set forth in Sections 1(d) and (e) shall not become effective unless
and until the Revolving Credit Commitment of all Lenders shall be reduced to an
amount less than or equal to $300,000,000 and each Lender's Revolving Credit
Commitment as of the date thereof shall be reduced as set forth in Section 2.3
of the Credit Agreement.

         Section 3.        Benefits of Loan Documents.

          Each reference to the Credit Agreement in any of the Loan Documents
shall be deemed to be a reference to the Credit Agreement as amended by this
Amendment, and as the Credit Agreement may from time to time be further amended,
supplemented, restated or otherwise modified in the future by one or more other
written amendments or supplemental or modification agreements entered into
pursuant to the applicable provisions thereof.

         Section 4.        Conditions to Effectiveness of Amendment.  The
effectiveness of this Amendment is subject to the condition precedent that each
of the following be received by the Agent (unless otherwise waived in writing by
the Agent), each of which shall be satisfactory in form and substance to the
Agent:

         (a)      this Amendment executed by the Borrower and by the Required
Lenders;

         (b)      the Acknowledgment and Consent of the Guarantors,
substantially in the form of Exhibit A hereto, executed by each of the
Guarantors (as defined below) (the "Acknowledgment");

         (c)      payment by the Borrower to the Agent, of any expenses incurred
by the Agent which are due and payable;

         (d)      no Default or Event of Default shall then be in existence; and

         (e)      such other approvals, opinions or documents as the Agent may
reasonably request.

         Section 5.        Representations.  The Borrower represents to the
Lenders that:

         (a)      The Borrower has the right and power, and has taken all
necessary action to authorize it, to execute and deliver this Amendment, and to
perform this Amendment, and the Credit Agreement, as amended by this Amendment,
in accordance with their respective terms. This Amendment has been duly executed
and delivered by the duly authorized officers of the Borrower, and each of this
Amendment, and the Credit Agreement, as amended by this Amendment, is a legal,
valid and binding obligation of the Borrower enforceable against the Borrower in
accordance with its terms, except as may be limited by applicable bankruptcy,
insolvency, reorganization, moratorium, or similar laws affecting the
enforcement of creditors' rights generally and by general principles of equity.

         (b)      The execution and delivery of this Amendment, and the
performance by the Borrower of this Amendment, and the Credit Agreement, as
amended by this Amendment, in accordance with their respective terms, do not and
will not, by the passage of time or the giving of notice, or otherwise: (i)
violate any Requirement of Law relating to the Borrower; (ii) conflict with,
result in a breach of or constitute a default under the charter or by-laws of
the Borrower, or any of its Material Contractual Obligations; or (iii) result in
or require the creation or imposition of any Lien upon or with respect to any
property now owned or hereafter acquired by the Borrower other than those
permitted by the Credit Agreement.

         (c)      The articles of incorporation and bylaws of the Borrower have
not changed since delivery of such articles of incorporation and bylaws to the
Lenders in connection with the consummation of the Credit Agreement.

         Section 6.        Reaffirmation.  The Borrower hereby repeats and
reaffirms all representations and warranties made by the Borrower in the Credit
Agreement and the other Loan Documents to which it is a party as of the date
hereof with the same force and effect as if such representations and warranties
were set forth in this Amendment in


                                      -4-
<PAGE>

full except to the extent such representations expressly relate to an earlier
date or have been updated to the extent permitted by the Credit Agreement.

         Section 7.        Reaffirmation and Representations by Guarantors.  By
execution of the Acknowledgment, each Subsidiary that has executed a Subsidiary
Guarantee (a "Guarantor"):

         (a)      reaffirms its continuing obligations to the Agent and the
Lenders under the Subsidiary Guarantee to which it is a party, and agrees that
the transactions contemplated by this Amendment shall not in any way affect the
validity and enforceability of such Subsidiary Guarantee, or reduce, impair or
discharge the obligations of such Guarantor thereunder; and

         (b)      represents to the Lenders that:

         (i)      Such Guarantor has the right and power, and has taken all
necessary action to authorize it, to execute and deliver this Acknowledgement,
and to perform this Acknowledgement in accordance with its terms. This
Acknowledgement has been duly executed and delivered by the duly authorized
officers of such Guarantor, and the Acknowledgement is a legal, valid and
binding obligation of such Guarantor enforceable against such Guarantor in
accordance with its terms, except as may be limited by applicable bankruptcy,
insolvency, reorganization, moratorium, or similar laws affecting the
enforcement of creditors' rights generally and by general principles of equity;
and

         (ii)     the execution and delivery of this Acknowledgement, and the
performance by such Guarantor of this Acknowledgement, do not and will not, by
the passage of time or the giving of notice, or otherwise: (i) violate any
Requirement of Law relating to such Guarantor; (ii) conflict with, result in a
breach of or constitute a default under the charter or by-laws of such
Guarantor, or any of its Material Contractual Obligations; or (iii) result in or
require the creation or imposition of any Lien upon or with respect to any
property now owned or hereafter acquired by such Guarantor other than those
permitted by the Credit Agreement.

         Section 8.        Benefits.  This Amendment shall be binding upon and
shall inure to the benefit of the parties hereto and their respective successors
and assigns.

         Section 9.        GOVERNING LAW.  THIS AMENDMENT SHALL BE GOVERNED BY,
AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF GEORGIA.

         Section 10.       Effect.  Except as expressly herein amended, the
terms and conditions of the Credit Agreement shall remain in full force and
effect.

         Section 11.       Counterparts.  This Amendment may be executed in any
number of counterparts, each of which shall be deemed to be an original and
shall be binding upon all parties.

                         [Signatures on following page]


                                      -5-
<PAGE>

         IN WITNESS WHEREOF, the parties have caused this Second Amendment to
Credit Agreement to be executed by their authorized officers all as of the day
and year first above written.

                                       ROCK-TENN COMPANY



(CORPORATE SEAL)                       By:
                                          -------------------------------------
                                          Title:
                                                -------------------------------

Attest:
By:
   ---------------------------------
   Title:

                       [Signatures Continued on Next Page]


                                      -6-
<PAGE>

            [SIGNATURE PAGE TO SECOND AMENDMENT TO CREDIT AGREEMENT]

                                       SUNTRUST BANK, AS AGENT, SWING LINE
                                       LENDER AND A LENDER



                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------

                                       WACHOVIA BANK, N.A., AS A LENDER AND
                                       DOCUMENTATION AGENT

                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------

                                       BANK OF AMERICA, N.A., AS A LENDER AND
                                       SYNDICATION AGENT



                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------

                                       THE CHASE MANHATTAN BANK,
                                       AS A LENDER



                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------

                                       THE BANK OF TOKYO-MITSUBISHI, LTD., AS A
                                       LENDER



                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------

                                       THE BANK OF NEW YORK,
                                       AS A LENDER



                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------

                       [Signatures Continued on Next Page]


                                      -7-
<PAGE>

            [SIGNATURE PAGE TO SECOND AMENDMENT TO CREDIT AGREEMENT]

                                       FIRST UNION NATIONAL BANK,
                                       AS A LENDER



                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------

                                       THE FUJI BANK, LIMITED,
                                       AS A LENDER



                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------

                                       BNP PARIBAS, AS A LENDER



                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------



                                       By:
                                          -------------------------------------
                                            Title:
                                                  -----------------------------


                                      -8-
<PAGE>

                                    EXHIBIT A

               ACKNOWLEDGMENT AND CONSENT OF SUBSIDIARY GUARANTORS

         Each of the undersigned Subsidiaries hereby (i) acknowledges receipt of
the foregoing Second Amendment to Credit Agreement by and among Rock-Tenn
Company, the Lenders under the Credit Agreement (the "Lenders") and SunTrust
Bank, in its capacity as Agent for the Lenders (the "Agent") (the "Amendment"),
(ii) consents to the Amendment, (iii) agrees and acknowledges to the terms
thereof including, without limitation, the representations and agreements of the
each of the undersigned set forth in Section 7 of the Amendment, and (iv)
restates and affirms its respective obligations under its Subsidiary Guarantee
previously executed and delivered in favor of the Agent (for the ratable benefit
of the Lenders) without defense, counterclaim or set-off.

         IN WITNESS WHEREOF, each of the undersigned Subsidiaries has executed
this Acknowledgment and Consent of Subsidiary Guarantors this 26th day of July,
2001.

                                       ROCK-TENN COMPANY, MILL DIVISION, a
                                       Tennessee corporation
                                       ROCK-TENN COMPANY OF TEXAS, a
                                       Georgia corporation
                                       ROCK-TENN COMPANY OF ARKANSAS, a
                                       Georgia corporation
                                       ROCK-TENN COMPANY OF CALIFORNIA, INC.,
                                       a Delaware corporation
                                       ROCK-TENN COMPANY OF ILLINOIS, INC.,
                                       an Illinois corporation
                                       ROCK-TENN CONVERTING COMPANY,
                                       a Georgia corporation
                                       CONCORD INDUSTRIES, INC.,
                                       an Illinois corporation
                                       WABASH CORPORATION, a Delaware
                                       corporation
                                       WALDORF CORPORATION, a Delaware
                                       corporation
                                       BEST RECYCLING, INC.,
                                       an Iowa corporation
                                       WALDORF REALTY, INC., a Delaware
                                       corporation
                                       ROCK-TENN PARTITION COMPANY,
                                       a Georgia corporation
                                       WALDORF CORPORATION OF MINNESOTA, a
                                       Delaware corporation



                                       By:
                                          -------------------------------------
                                          Name:
                                               --------------------------------
                                          Title:
                                                -------------------------------


                                      -9-