SECURITIES & EXCHANGE COMMISSION
                             Washington, D.C. 20549
                             ----------------------

                                  SCHEDULE 13G*
                                 (Rule 13d-102)

             INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
           TO RULES 13d-1(b), (c) AND (d) AND AMENDMENTS THERETO FILED
                              PURSUANT TO 13d-2(b)
                                (Amendment No. 1)

                            Regal-Beloit Corporation
                                (Name of Issuer)

                          Common Stock, $.01 Par Value
                         (Title of Class of Securities)

                                    758750103
                                 (CUSIP Number)

                                December 31, 2007
             (Date of event which requires filing of this statement)


     Check the appropriate box to designate the rule pursuant to which this
Schedule 13G is filed:
     [ ]  Rule 13d-1(b)
     [X]  Rule 13d-1(c)
     [ ]  Rule 13d-1(d)





                              (Page 1 of 11 Pages)
----------------
     *The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.

     The information required in the remainder of this cover page shall not be
deemed to be "filed" for purposes of Section 18 of the Securities Exchange Act
of 1934 ("Act") or otherwise subject to the liabilities of that section of the
Act but shall be subject to all other provisions of the Act (however, see the
Notes).





CUSIP No. 758750103                13G/A                   Page 2 of 11 Pages

-----------------------------------------------------------------------------
     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO.
            OF ABOVE PERSONS (ENTITIES ONLY)
                                           Adage Capital Partners, L.P.
-----------------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP **
                                                                  (a)  [ ]
                                                                  (b)  [X]
-----------------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION
                             Delaware
-----------------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                                                -0-
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,365,970 shares of Common Stock
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                                                -0-
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED
            BY EACH REPORTING PERSON
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT
            IN ROW (9) EXCLUDES CERTAIN SHARES **                       [ ]
-----------------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
                                                4.3%
-----------------------------------------------------------------------------
     (12)   TYPE OF REPORTING PERSON **
                                                PN
-----------------------------------------------------------------------------
                     ** SEE INSTRUCTIONS BEFORE FILLING OUT!





CUSIP No. 758750103                13G/A                   Page 3 of 11 Pages

-----------------------------------------------------------------------------
     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO.
            OF ABOVE PERSONS (ENTITIES ONLY)
                                           Adage Capital Partners GP, L.L.C.
-----------------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP **
                                                                  (a)  [ ]
                                                                  (b)  [X]
-----------------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION
                             Delaware
-----------------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                                                -0-
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,365,970 shares of Common Stock
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                                                -0-
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED
            BY EACH REPORTING PERSON
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT
            IN ROW (9) EXCLUDES CERTAIN SHARES **                       [ ]
-----------------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
                                                4.3%
-----------------------------------------------------------------------------
     (12)   TYPE OF REPORTING PERSON **
                                                OO
-----------------------------------------------------------------------------
                     ** SEE INSTRUCTIONS BEFORE FILLING OUT!





CUSIP No. 758750103                13G/A                   Page 4 of 11 Pages

-----------------------------------------------------------------------------
     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO.
            OF ABOVE PERSONS (ENTITIES ONLY)
                                           Adage Capital Advisors, L.L.C.
-----------------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP **
                                                                  (a)  [ ]
                                                                  (b)  [X]
-----------------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION
                             Delaware
-----------------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                                                -0-
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,365,970 shares of Common Stock
OWNED BY       ___________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                                                -0-
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED
            BY EACH REPORTING PERSON
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT
            IN ROW (9) EXCLUDES CERTAIN SHARES **                       [ ]
-----------------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
                                                4.3%
-----------------------------------------------------------------------------
     (12)   TYPE OF REPORTING PERSON **
                                                OO
-----------------------------------------------------------------------------
                     ** SEE INSTRUCTIONS BEFORE FILLING OUT!





CUSIP No. 758750103                13G/A                   Page 5 of 11 Pages

-----------------------------------------------------------------------------
     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO.
            OF ABOVE PERSONS (ENTITIES ONLY)
                                                     Robert Atchinson
-----------------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP **
                                                                  (a)  [ ]
                                                                  (b)  [X]
-----------------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION
                             United States
-----------------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                                                -0-
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,365,970 shares of Common Stock
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                                                -0-
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED
            BY EACH REPORTING PERSON
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT
            IN ROW (9) EXCLUDES CERTAIN SHARES **                       [ ]
-----------------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
                                                4.3%
-----------------------------------------------------------------------------
     (12)   TYPE OF REPORTING PERSON **
                                                IN
-----------------------------------------------------------------------------
                     ** SEE INSTRUCTIONS BEFORE FILLING OUT!





CUSIP No. 758750103                13G/A                   Page 6 of 11 Pages

-----------------------------------------------------------------------------
     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO.
            OF ABOVE PERSONS (ENTITIES ONLY)
                                                     Phillip Gross
-----------------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP **
                                                                  (a)  [ ]
                                                                  (b)  [X]
-----------------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION
                             United States
-----------------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                                                -0-
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,365,970 shares of Common Stock
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                                                -0-
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED
            BY EACH REPORTING PERSON
                    1,365,970 shares of Common Stock
-----------------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT
            IN ROW (9) EXCLUDES CERTAIN SHARES **                       [ ]
-----------------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
                                                4.3%
-----------------------------------------------------------------------------
     (12)   TYPE OF REPORTING PERSON **
                                                IN
-----------------------------------------------------------------------------
                     ** SEE INSTRUCTIONS BEFORE FILLING OUT!





CUSIP No. 758750103                13G/A                   Page 7 of 11 Pages


Item 1(a).     Name of Issuer:

     The name of the issuer is Regal-Beloit Corporation (the "Company").

Item 1(b).     Address of Issuer's Principal Executive Offices:

     The Company's principal executive offices are located at 200 State Street,
Beloit, WI 53511


Item 2(a).     Name of Person Filing:

     This statement is filed by:
          (i) Adage Capital Partners, L.P., a Delaware limited partnership
              ("ACP"), with respect to the shares of Common Stock beneficially
              owned by it;
         (ii) Adage Capital Partners GP, L.L.C., a limited liability company
              organized under the laws of the State of Delaware ("ACPGP"), as
              general partner of ACP with respect to the shares of Common Stock
              beneficially owned by ACP;
        (iii) Adage Capital Advisors, L.L.C., a limited liability company
              organized under the laws of the State of Delaware ("ACA"), as
              managing member of ACPGP, general partner of ACP, with respect to
              the shares of Common Stock beneficially owned by ACP;
         (iv) Phillip Gross ("Mr. Gross"), as managing member of ACA, managing
              member of ACPGP, general partner of ACP with respect to the
              shares of Common Stock beneficially owned by ACP; and
          (v) Robert Atchinson ("Mr. Atchinson"), as managing member of ACA,
              managing member of ACPGP, general partner of ACP with respect to
              the shares of Common Stock beneficially owned by ACP.

     The foregoing persons are hereinafter collectively referred to as the
"Reporting Persons." Any disclosures herein with respect to persons other than
the Reporting Persons are made on information and belief after making inquiry to
the appropriate party.

Item 2(b).     Address of Principal Business Office or, if None, Residence:

     The address of the business office of each of the Reporting Persons is 200
Clarendon Street, 52nd Floor, Boston, Massachusetts 02116.

Item 2(c).     Citizenship:

     ACP is a limited partnership organized under the laws of the State of
Delaware. ACPGP and ACA are limited liability companies organized under the laws
of the State of Delaware. Messrs. Gross and Atchinson are citizens of the United
States.

Item 2(d).     Title of Class of Securities:

     Common Stock, $.01 Par Value (the "Common Stock")





CUSIP No. 758750103                13G/A                   Page 8 of 11 Pages


Item 2(e).     CUSIP Number:

     758750103

Item 3. If this statement is filed pursuant to Rules 13d-1(b) or 13d-2(b) or
(c), check whether the person filing is a:

          (a) [ ]  Broker or dealer registered under Section 15 of the
                   Act,

          (b) [ ]  Bank as defined in Section 3(a)(6) of the Act,

          (c) [ ]  Insurance Company as defined in Section 3(a)(19) of
                   the Act,

          (d) [ ]  Investment Company registered under Section 8 of the
                   Investment Company Act of 1940,

          (e) [ ]  Investment Adviser in accordance with Rule
                   13d-1 (b)(1)(ii)(E),

          (f) [ ]  Employee Benefit Plan or Endowment Fund in accordance
                   with 13d-1 (b)(1)(ii)(F),

          (g) [ ]  Parent Holding Company or control person in accordance
                   with Rule 13d-1 (b)(1)(ii)(G),

          (h) [ ]  Savings Association as defined in Section 3(b) of the
                   Federal Deposit Insurance Act,

          (i) [ ]  Church Plan that is excluded from the definition of an
                   investment company under Section 3(c)(14) of the
                   Investment Company Act of 1940,

          (j) [ ]  Group, in accordance with Rule 13d-1(b)(1)(ii)(J).

     If this statement is filed pursuant to 13d-1(c), check this box:  [x]

Item 4.   Ownership.

      A. Adage Capital Partners, L.P., Adage Capital Partners GP, L.L.C. and
Adage Capital Advisors, L.L.C.
              (a) Amount beneficially owned:
                  1,365,970 shares of Common Stock

              (b) Percent of class: 4.3% The percentages used herein and in the
                  rest of Item 4 are calculated based upon the 32,098,630 shares
                  of Common Stock issued and outstanding on October 26, 2007 as
                  reflected in the Form 10-Q of the Company filed on November 6,
                  2007.

              (c)(i) Sole power to vote or direct the vote: -0-
                (ii) Shared power to vote or direct the vote:
                     1,365,970 shares of Common Stock
               (iii) Sole power to dispose or direct the disposition: -0-
                (iv) Shared power to dispose or direct the disposition:
                     1,365,970 shares of Common Stock





CUSIP No. 758750103                13G/A                   Page 9 of 11 Pages


      ACP has the power to dispose of and the power to vote the shares of Common
Stock beneficially owned by it, which power may be exercised by its general
partner, ACPGP. ACA, as managing member of ACPGP, directs ACPGP's operations.
Neither ACPGP nor ACA owns directly any shares of Common Stock. By reason of the
provisions of Rule 13d-3 of the Securities Exchange Act of 1934 (the "Act"),
ACPGP and ACA may be deemed to own beneficially the shares of Common Stock
beneficially owned by ACP.


      B. Robert Atchinson and Phillip Gross
              (a) Amount beneficially owned:
                  1,365,970 shares of Common Stock

              (b) Percent of class: 4.3%

              (c)(i) Sole power to vote or direct the vote: -0-
                (ii) Shared power to vote or direct the vote:
                     1,365,970 shares of Common Stock
               (iii) Sole power to dispose or direct the disposition: -0-
                (iv) Shared power to dispose or direct the disposition:
                     1,365,970 shares of Common Stock

      Messrs. Atchinson and Gross, as managing members of ACA, have shared power
to vote the Common Stock beneficially owned by ACP. Neither Mr. Atchinson nor
Mr. Gross directly owns any shares of Common Stock. By reason of the provisions
of Rule 13d-3 of the Act, each may be deemed to beneficially own the shares of
Common Stock beneficially owned by ACP.

Item 5.   Ownership of Five Percent or Less of a Class.

      If this statement is being filed to report the fact as of the date hereof
the reporting person has ceased to be the beneficial owner of more than five
percent of the class of securities, check the following [X].

Item 6.   Ownership of More than Five Percent on Behalf of Another Person.

      Not applicable.

Item 7.   Identification and Classification of the Subsidiary Which Acquired
the Security Being Reported on by the Parent Holding Company.

      Not applicable.

Item 8.   Identification and Classification of Members of the Group.

      Not applicable.

Item 9.   Notice of Dissolution of Group.

      Not applicable.

Item 10.  Certification.

      Each of the Reporting Persons hereby makes the following certification:

          By signing below each Reporting Person certifies that, to the best





CUSIP No. 758750103                13G/A                   Page 10 of 11 Pages


of its knowledge and belief, the securities referred to above were not acquired
and are not held for the purpose of or with the effect of changing or
influencing the control of the issuer of the securities and were not acquired
and are not held in connection with or as a participant in any transaction
having that purpose or effect.





CUSIP No. 758750103                13G/A                   Page 11 of 11 Pages


                                   SIGNATURES

After reasonable inquiry and to the best of our knowledge and belief, the
undersigned certify that the information set forth in this statement is true,
complete and correct.


DATED:  February 11, 2008

                                ADAGE CAPITAL PARTNERS, L.P.

                                By:  Adage Capital Partners GP, L.L.C.,
                                     its general partner

                                By:  Adage Capital Advisors, L.L.C.,
                                     its managing member

                                /s/ Robert Atchinson
                                ------------------------------
                                Name:  Robert Atchinson
                                Title: Managing Member


                                ADAGE CAPITAL PARTNERS GP, L.L.C.
                                By:  Adage Capital Advisors, L.L.C.,
                                     its managing member

                                /s/ Robert Atchinson
                                ------------------------------
                                Name:  Robert Atchinson
                                Title: Managing Member


                                ADAGE CAPITAL ADVISORS, L.L.C.

                                /s/ Robert Atchinson
                                ------------------------------
                                Name:  Robert Atchinson
                                Title: Managing Member


                                ROBERT ATCHINSON

                                /s/ Robert Atchinson
                                ------------------------------
                                ROBERT ATCHINSON, individually


                                PHILLIP GROSS

                                /s/ Phillip Gross
                                ------------------------------
                                PHILLIP GROSS, individually