Document:

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                                                                     Exhibit 4.1

                    SECOND AMENDMENT TO THE RIGHTS AGREEMENT

      THIS SECOND AMENDMENT TO RIGHTS AGREEMENT (this "Amendment"), is dated as
of May 19, 2004, between Advanced Fibre Communications, Inc., a Delaware
corporation (the "Company"), and Equiserve Trust Company, N.A. (the "Rights
Agent").

      WHEREAS, the Company and the Rights Agent (as the successor in interest to
BankBoston, N.A.) are parties to a Rights Agreement, dated as of May 13, 1998,
as amended by the First Amendment thereto, dated as of October 19, 1998 (the
"Rights Agreement"); and

      WHEREAS, pursuant to Section 27 of the Rights Agreement, the Company and
the Rights Agent desire to amend the Rights Agreement as set forth below;

      NOW, THEREFORE, the Rights Agreement is hereby amended as follows:

      1.    Amendment of Section 1.

      Section 1 of the Rights Agreement is amended by adding thereto a new
definition immediately after the definition of "Final Expiration Date" and
immediately before the definition of "NASDAQ" which new definition shall read as
follows:

      "'Merger Agreement' shall mean the Agreement and Plan of Merger, dated as
      of May 19, 2004, among Tellabs, Inc., Chardonnay Merger Corp. and the
      Company, as the same may be amended from time to time."

      2.    Amendment of Section 7.

      Section 7(a) of the Rights Agreement is amended by amending the definition
of "Expiration Date" by deleting the phrase which begins with the word "or"
immediately preceding clause (iii) thereof and ends with the "." at the end of
Section 7(a) and replacing it with the phrase:

      "(iii) the time at which such Rights are exchanged as provided in Section
      24 hereof, or (iv) immediately prior to the Effective Time (as defined in
      the Merger Agreement) (the earliest of (i), (ii), (iii) and (iv) being the
      "Expiration Date")."

      3.    Addition of New Section 35.

      The Rights Agreement is amended by adding a Section 35 immediately after
Section 34 which shall read as follows:
<PAGE>
      "Section 35. Exception for Merger Agreement. Notwithstanding any provision
      of this Agreement to the contrary, (i) no Distribution Date, Shares
      Acquisition Date or Triggering Event shall be deemed to have occurred,
      (ii) none of Parent, Sub, or Sister Subsidiary (each as defined in the
      Merger Agreement), nor any of their Subsidiaries, Affiliates or Associates
      (collectively, the "Acquisition Group"), shall be deemed to have become an
      Acquiring Person, and (iii) no holder of Rights shall be entitled to
      exercise such Rights under, or be entitled to any rights or benefits
      pursuant to, any of Sections 3, 7, 11 or 13, or any other provision of
      this Agreement, in each case solely by reason of (a) the approval,
      execution, delivery and performance of the Merger Agreement, (b)
      consummation of any of the transactions contemplated by the Merger
      Agreement, including, without limitation, the Merger and the Subsequent
      Merger (each as defined in the Merger Agreement), in accordance with the
      provisions of the Merger Agreement, or (c) the announcement of any of
      foregoing; provided that in the event that one or more members of the
      Acquisition Group collectively become the Beneficial Owner of 15% or more
      of the shares of Common Stock then outstanding in any manner other than as
      set forth in the Merger Agreement, the provisions of this Section 35
      (other than this proviso) shall terminate."

      4.    Effectiveness.

            This Amendment shall be deemed effective as of May 19, 2004 as if
executed by both parties hereto on such date. Except as amended hereby, the
Rights Agreement shall remain in full force and effect and shall be otherwise
unaffected hereby.

      5.    Miscellaneous.

            This Amendment shall be deemed to be a contract made under the laws
of the State of Delaware and for all purposes shall be governed by and construed
in accordance with the laws of such state applicable to contracts to be made and
performed entirely within such state. This Amendment may be executed in any
number of counterparts, each of such counterparts shall for all purposes be
deemed to be an original, and all such counterparts shall together constitute
but one and the same instrument. If any term, provision, covenant or restriction
of this Amendment is held by a court of competent jurisdiction or other
authority to be invalid, illegal, or unenforceable, the remainder of the terms,
provisions, covenants and restrictions of this Amendment shall remain in full
force and effect and shall in no way be affected, impaired or invalidated.

            [The remainder of this page is intentionally left blank.]
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      IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the date set forth above.

                         ADVANCED FIBRE COMMUNICATIONS, INC.

                         By:        /s/ John A. Schofield
                             ----------------------------------
                             Name:  John A. Schofield
                             Title: Chief Executive Officer and President

                         EQUISERVE TRUST COMPANY, N.A.

                         By:        /s/ Dennis V. Moccia
                             ----------------------------------
                             Name:  Dennis V. Moccia
                             Title: Managing Director<PAGE>

DCB FINANCIAL CORP - 8-K                                   Filing Date: 5/20/04
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                                  EXHIBIT 10.1
FOR IMMEDIATE RELEASE                                  CONTACT:
Thursday May 20, 2004                                  John A. Ustaszewski
                                                       Chief Financial Officer
                                                       (740) 657-7000

                  DCB FINANCIAL CORP ANNOUNCES SPECIAL DIVIDEND

Lewis Center, Ohio - The Board of Directors of DCB Financial Corp announced a
special dividend of $.05 per common share to shareholders of record May 28, 2004
payable June 16, 2004.

In April, DCB Financial Corp announced that it would record an after tax gain to
second quarter earnings of approximately $1.6 million as a result of the sale of
its investment in ProCentury Corporation. In addition to using the proceeds for
general corporate purposes and reducing corporate debt, the Board of Directors
declared the special divided.

 "The investors in our Company have been very supportive and loyal over the
years and this is one small way we can recognize that", said G. William Parker,
Chairman.

DCB Financial Corp is the parent company of The Delaware County Bank & Trust
Company which operates 15 branch offices in Delaware, Union and Franklin
Counties, Ohio.

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                               Disclosure Page 3

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DCB FINANCIAL CORP - 8-K                                   Filing Date: 5/20/04
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DCB Financial Corp (the "Corporation") is a financial holding company formed
under the laws of the State of Ohio. The Corporation is the parent of The
Delaware County Bank & Trust Company, (the "Bank") a state-chartered commercial
bank. The Bank conducts business from its main offices at 110 Riverbend Avenue
in Lewis Center, Ohio, and through its 15 full-service branch offices located in
Delaware and the surrounding communities. The Bank provides customary retail and
commercial banking services to its customers, including checking and savings
accounts, time deposits, IRAs, safe deposit facilities, personal loans,
commercial loans, real estate mortgage loans, night depository facilities and
trust services. The Bank also provides cash management, bond registrar and
payment services. The Bank offers data processing services to other financial
institutions, however such services are not a significant part of its current
operations or revenues.

APPLICATION OF CRITICAL ACCOUNTING POLICIES
DCB's consolidated financial statements are prepared in accordance with
accounting principles generally accepted in the United States and follow general
practices within the financial services industry. The application of these
principles requires management to make estimates, assumptions, and judgments
that affect the amounts reported in the financial statements and accompanying
notes. These estimates, assumptions, and judgments are based on information
available as of the date of the financial statements; as this information
changes, the financial statements could reflect different estimates,
assumptions, and judgments.

The most significant accounting policies followed by the Corporation are
presented in Note 1 of the audited consolidated financial statements contained
in the Corporation's 2003 Annual Report to Shareholders. These policies, along
with the disclosures presented in the other financial statement notes and in
this financial review, provide information on how significant assets and
liabilities are valued in the financial statements and how those values are
determined.

FORWARD-LOOKING STATEMENTS
Certain statements in this report constitute "forward-looking statements" within
the meaning of the Private Securities Litigation Reform Act of 1995, such as
statements relating to the financial condition and prospects, lending risks,
plans for future business development and marketing activities, capital spending
and financing sources, capital structure, the effects of regulation and
competition, and the prospective business of both the Corporation and its
wholly-owned subsidiary The Delaware County Bank & Trust Company (the "Bank").
Where used in this report, the word "anticipate," "believe," "estimate,"
"expect," "intend," and similar words and expressions, as they relate to the
Corporation or the Bank or their respective management, identify forward-looking
statements. Such forward-looking statements reflect the current views of the
Corporation and are based on information currently available to the management
of the Corporation and the Bank and upon current expectations, estimates, and
projections about the Corporation and its industry, management's belief with
respect thereto, and certain assumptions made by management. These
forward-looking statements are not guarantees of future performance and are
subject to risks, uncertainties, and other factors that could cause actual
results to differ materially from those expressed or implied by such
forward-looking statements. Potential risks and uncertainties include, but are
not limited to: (i) significant increases in competitive pressure in the banking
and financial services industries; (ii) changes in the interest

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                               Disclosure Page 4

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DCB FINANCIAL CORP - 8-K                                   Filing Date: 5/20/04
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rate environment which could reduce anticipated or actual margins; (iii) changes
in political conditions or the legislative or regulatory environment; (iv)
general economic conditions, either nationally or regionally (especially in
central Ohio), becoming less favorable than expected resulting in, among other
things, a deterioration in credit quality of assets; (v) changes occurring in
business conditions and inflation; (vi) changes in technology; (vii) changes in
monetary and tax policies; (viii) changes in the securities markets; and (ix)
other risks and uncertainties detailed from time to time in the filings of the
Corporation with the Commission.

The Corporation does not undertake, and specifically disclaims any obligation,
to publicly revise any forward-looking statements to reflect events or
circumstances after the date of such statements or to reflect the occurrence of
anticipated or unanticipated events.

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                               Disclosure Page 5

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