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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
 Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
 (Amendment No. 1)
Wilson Greatbatch Technologies Inc.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

972232102

(CUSIP Number)

December 31, 2001

(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:
[ X ] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)
*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 the purpose 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).
PAGE 1 OF 11 PAGES

-----------------------------------------                                        --------------------------------------
CUSIP No.   972232102                                      13G                   Page  2  of  11  Pages
-----------------------------------------                                        --------------------------------------

---------- -------------------------------------------------------------------------------------------------------------
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           John Hancock Financial Services, Inc.
           I.R.S. No. 04-3483032

---------- -------------------------------------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                      (a)  |_|
                                                                                  (b)  |_|
           N/A

---------- -------------------------------------------------------------------------------------------------------------
    3      SEC USE ONLY

---------- -------------------------------------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware

---------- -------------------------------------------------------------------------------------------------------------
                       5     SOLE VOTING POWER
    Number of
      Shares                 -0-

                    -------- -------------------------------------------------------------------------------------------
   Beneficially        6     SHARED VOTING POWER
     Owned by
       Each                  -0-

                    -------- -------------------------------------------------------------------------------------------
    Reporting          7     SOLE DISPOSITIVE POWER
      Person
       With                  -0-

                    -------- -------------------------------------------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-

---------- -------------------------------------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           None, except through its indirect, wholly-owned subsidiary, John Hancock Advisers, LLC

---------- -------------------------------------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A

--------- -------------------------------------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           See line 9, above.

---------- -------------------------------------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           HC

---------- -------------------------------------------------------------------------------------------------------------
                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                               PAGE 2 OF 11 PAGES	

-----------------------------------------                                        --------------------------------------
CUSIP No.   972232102                                      13G                   Page  3  of  11  Pages
-----------------------------------------                                        --------------------------------------

---------- -------------------------------------------------------------------------------------------------------------
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           John Hancock Life Insurance Company
           I.R.S. No. 04-1414660

---------- -------------------------------------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                      (a)  |_|
                                                                                  (b)  |_|
           N/A

---------- -------------------------------------------------------------------------------------------------------------
    3      SEC USE ONLY

---------- -------------------------------------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Commonwealth of Massachusetts

---------- -------------------------------------------------------------------------------------------------------------
                       5     SOLE VOTING POWER
    Number of
      Shares                 -0-

                    -------- -------------------------------------------------------------------------------------------
   Beneficially        6     SHARED VOTING POWER
     Owned by
       Each                  -0-

                    -------- -------------------------------------------------------------------------------------------
    Reporting          7     SOLE DISPOSITIVE POWER
      Person
       With                  -0-

                    -------- -------------------------------------------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-

---------- -------------------------------------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           None, except through its indirect, wholly-owned subsidiary, John Hancock Advisers, LLC

---------- -------------------------------------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A

---------- -------------------------------------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           See line 9, above.

---------- -------------------------------------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IC, IA, HC

---------- -------------------------------------------------------------------------------------------------------------
                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                               PAGE 3 OF 11 PAGES	

-----------------------------------------                                        --------------------------------------
CUSIP No.   972232102                                      13G                   Page  4  of  11  Pages
-----------------------------------------                                        --------------------------------------

---------- -------------------------------------------------------------------------------------------------------------
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           John Hancock Subsidiaries LLC
           I.R.S. No. 04-2687223

---------- -------------------------------------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                      (a)  |_|
                                                                                  (b)  |_|
           N/A

---------- -------------------------------------------------------------------------------------------------------------
    3      SEC USE ONLY

---------- -------------------------------------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware

---------- -------------------------------------------------------------------------------------------------------------
                       5     SOLE VOTING POWER
    Number of
      Shares                 -0-

                    -------- -------------------------------------------------------------------------------------------
   Beneficially        6     SHARED VOTING POWER
     Owned by
       Each                  -0-

                    -------- -------------------------------------------------------------------------------------------
    Reporting          7     SOLE DISPOSITIVE POWER
      Person
       With                  -0-

                    -------- -------------------------------------------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-

---------- -------------------------------------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           None, except through its indirect, wholly-owned subsidiary, John Hancock Advisers, LLC

---------- -------------------------------------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A

---------- -------------------------------------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           See line 9, above.

---------- -------------------------------------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           HC

---------- -------------------------------------------------------------------------------------------------------------
                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                               PAGE 4 OF 11 PAGES	

-----------------------------------------                                        --------------------------------------
CUSIP No.   972232102                                      13G                   Page  5  of  11  Pages
-----------------------------------------                                        --------------------------------------

---------- -------------------------------------------------------------------------------------------------------------
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           The Berkeley Financial Group, LLC
           I.R.S. No. 04-3145626

---------- -------------------------------------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                      (a)  |_|
                                                                                  (b)  |_|
           N/A

---------- -------------------------------------------------------------------------------------------------------------
    3      SEC USE ONLY

---------- -------------------------------------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware

---------- -------------------------------------------------------------------------------------------------------------
                       5     SOLE VOTING POWER
    Number of
      Shares                 -0-

                    -------- -------------------------------------------------------------------------------------------
   Beneficially        6     SHARED VOTING POWER
     Owned by
       Each                  -0-

                    -------- -------------------------------------------------------------------------------------------
    Reporting          7     SOLE DISPOSITIVE POWER
      Person
       With                  -0-

                    -------- -------------------------------------------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-

---------- -------------------------------------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           None, except through its indirect, wholly-owned subsidiary, John Hancock Advisers, LLC

---------- -------------------------------------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A

---------- -------------------------------------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           See line 9, above.

---------- -------------------------------------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           HC

---------- -------------------------------------------------------------------------------------------------------------
                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                               PAGE 5 OF 11 PAGES	

-----------------------------------------                                        --------------------------------------
CUSIP No.   972232102                                      13G                   Page  6  of  11  Pages
-----------------------------------------                                        --------------------------------------

---------- -------------------------------------------------------------------------------------------------------------
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           John Hancock Advisers, LLC
           I.R.S. No. 04-2441573

---------- -------------------------------------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                      (a)  |_|
                                                                                  (b)  |_|
           N/A

---------- -------------------------------------------------------------------------------------------------------------
    3      SEC USE ONLY

---------- -------------------------------------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware

---------- -------------------------------------------------------------------------------------------------------------
                       5     SOLE VOTING POWER
    Number of
      Shares                 953,130

                    -------- -------------------------------------------------------------------------------------------
   Beneficially        6     SHARED VOTING POWER
     Owned by
       Each                  -0-

                    -------- -------------------------------------------------------------------------------------------
    Reporting          7     SOLE DISPOSITIVE POWER
      Person
       With                  953,130

                    -------- -------------------------------------------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-

---------- -------------------------------------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           953,130

---------- -------------------------------------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A

---------- -------------------------------------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           4.6%

---------- -------------------------------------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA

---------- -------------------------------------------------------------------------------------------------------------
                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                               PAGE 6 OF 11 PAGES	

         The original statement shall be signed by each person on whose behalf
the statement is filed or his authorized representative. If the statement is
signed on behalf of a person by his authorized representative other than an
executive officer or general partner of the filing person, evidence of the
representative's authority to sign on behalf of such person shall be filed with
the statement, provided, however, that a power of attorney for this purpose
which is already on file with the Commission may be incorporated by reference.
The name and any title of each person who signs the statement shall be typed or
printed beneath his signature.

Note: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Sec. 240.13d-7 for other
parties for whom copies are to be sent.

         Attention: Intentional misstatements or omissions of fact constitute
Federal criminal violations (See 18 U.S.C. 1001)

         Item 1(a)    Name of Issuer:
                      --------------
                      Wilson Greatbatch Technologies Inc.

         Item 1(b)    Address of Issuer's Principal Executive Offices:
                      -----------------------------------------------
                      10,000 Wehrle Drive
                      Clarence, NY  14031

         Item 2(a)    Name of Person Filing:
                      ---------------------
                      This filing is made on behalf of John Hancock Financial
                      Services, Inc. ("JHFS"), JHFS's direct, wholly-owned
                      subsidiary, John Hancock Life Insurance Company
                      ("JHLICO"), JHLICO's direct, wholly-owned subsidiary, John
                      Hancock Subsidiaries LLC ("JHS"), JHS's direct,
                      wholly-owned subsidiary, The Berkeley Financial Group, LLC
                      ("TBFG") and TBFG's wholly-owned subsidiary, John Hancock
                      Advisers, LLC ("JHA").

         Item 2(b)    Address of the Principal Offices:
                      --------------------------------
                      The principal business offices of JHFS, JHLICO and JHS are
                      located at John Hancock Place, P.O. Box 111, Boston, MA
                      02117. The principal business offices of TBFG and JHA are
                      located at 101 Huntington Avenue, Boston, Massachusetts
                      02199.

         Item 2(c)    Citizenship:
                      -----------
                      JHLICO was organized and exists under the laws of the
                      Commonwealth of Massachusetts. JHFS, JHS, TBFG and JHA
                      were organized and exist under the laws of the State of
                      Delaware.

         Item 2(d)    Title of Class of Securities:
                      ----------------------------
                      Common Stock

         Item 2(e)    CUSIP Number:
                      -------------
                      972232102

         Item 3       If the Statement is being filed pursuant to Rule
                      ------------------------------------------------
                      13d-1(b), or 13d-2(b), check whether the person filing is a:
                      ------------------------------------------------------------

                      JHFS:         (g) (X) Parent Holding Company, in accordance with
                                            ss.240.13d-1(b)(ii)(G).

                      JHLICO:       (c) (X) Insurance Company as defined in ss.3(a)(19) of the Act.

                                    (e) (X) Investment Adviser registered under ss.203 of the
                                            Investment Advisers Act of 1940.

                               PAGE 7 OF 11 PAGES	

                                    (g) (X) Parent Holding Company, in accordance with
                                            ss.240.13d-1(b)(ii)(G).

                      JHS:          (g) (X) Parent Holding Company, in accordance with
                                            ss.240.13d-1(b)(ii)(G).

                      TBFG:         (g) (X) Parent Holding Company, in accordance with
                                            ss.240.13d-1(b)(ii)(G).

                      JHA:          (e) (X) Investment Adviser registered under ss.203 of the
                                            Investment Advisers Act of 1940.

         Item 4       Ownership:
                      ---------

                      (a)  Amount Beneficially Owned: JHA has direct beneficial
                           ownership of 953,130 shares of Common Stock. Through
                           their parent-subsidiary relationship to JHA, JHFS,
                           JHLICO, JHS and TBFG have indirect, beneficial
                           ownership of these same shares.

                      (b)    Percent of Class: 4.6%
                             ----------------

                      (c)    (i)    sole power to vote or to direct the vote:
                                    JHA has sole power to vote or to direct the
                                    vote of 953,130 shares of Common Stock under
                                    the Advisory Agreements as follows:

                                                                                        Number    Date of Advisory
                         Fund Name                                                     of Shares  Agreement
                         ---------                                                     ---------  ---------
                         John Hancock Small Cap Growth Fund                             502,500   December 02, 1996
                         Variable Series Trust I - Small Cap Growth Portfolio           70,400    March 29, 1996
                         John Hancock Health Sciences Fund                              120,000   June 24, 1991
                         Parochial Employees Retirement System of Louisiana             10,450    August 21, 2000
                         UFF Croissance Amerique                                        29,700    October 06, 1997
                         John Hancock Multi Cap Growth Fund                              2,300    June 01, 1999
                         Deere & Company                                                18,100    October 01, 2000
                         Maritime Life Discovery Fund                                   32,000    May 11, 1994
                         D&H Local 372                                                   2,450    September 29, 2000
                         Verizon Small Cap Growth                                       101,900   October 12, 2001
                         John Hancock Small Cap Growth-2J                                5,100    November 01, 1998
                         John Hancock Focused Small Cap Growth                           4,960    December 11, 1995
                         Plumbers Union Local No. 12                                     1,550    December 20, 2000
                         Verizon Savings Trust SCG                                      30,900    December 21, 2001
                         John Hancock Small Cap Growth-5A                               19,900    November 01, 1998
                         Various Private Accounts                                         920

                             (ii)   shared power to vote or to direct the vote:  -0-

                             (iii)  sole power to dispose or  to direct the disposition of:
                                    JHA has sole power to dispose or to direct
                                    the disposition of 953,130 shares of Common
                                    Stock under the Advisory Agreement noted in
                                    Item 4(c)(i) above.

                             (iv)   shared power to dispose or to direct the disposition of:  -0-

         Item 5       Ownership of Five Percent or Less of a Class:
                      --------------------------------------------
                      If this statement is being filed to report the fact that
                      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:
                      ---------------------------------------------------------------
                      See Item 4.

                               PAGE 8 OF 11 PAGES	

         Item 7       Identification and Classification of the Subsidiary which Acquired
                      ------------------------------------------------------------------
                      the Security Being Reported on by the Parent Holding Company:
                      -------------------------------------------------------------
                      See Items 3 and 4 above.

         Item 8       Identification and Classification of Members of the Group:
                      ---------------------------------------------------------
                      Not applicable.

         Item 9       Notice of Dissolution of a Group:
                      --------------------------------
                      Not applicable.

         Item 10      Certification:
                      -------------
                      By signing below the undersigned certifies that, to the
                      best of its knowledge and belief, the securities referred
                      to above were acquired in the ordinary course of business
                      and were not acquired for the purpose of and do not have
                      the effect of changing or influencing the control of the
                      issuer of such securities and were not acquired in
                      connection with or as a participant in any transaction
                      having such purpose or effect.

                               PAGE 9 OF 11 PAGES	

                                    SIGNATURE

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

                                                     John Hancock Financial Services, Inc.

                                                     By:      /s/Barry J. Rubenstein
                                                              ----------------------
                                                              Name:    Barry J. Rubenstein
Dated:  February 6, 2002                                      Title:   Vice President, Counsel & Secretary

                                                     John Hancock Life Insurance Company

                                                     By:      /s/Gregory P. Winn
                                                              ------------------
                                                              Name:    Gregory P. Winn
Dated:  February 6, 2002                                      Title:   Vice President & Treasurer

                                                     John Hancock Subsidiaries LLC

                                                     By:      /s/Gregory P. Winn
                                                              ------------------
                                                              Name:    Gregory P. Winn
Dated:  February 6, 2002                                      Title:   Treasurer

                                                     The Berkeley Financial Group, LLC

                                                     By:      /s/Susan S. Newton
                                                              ------------------
                                                              Name:    Susan S. Newton
Dated:  February 6, 2002                                      Title:   Senior Vice President

                                                     John Hancock Advisers, LLC

                                                     By:      /s/Susan S. Newton
                                                              ------------------
                                                              Name:    Susan S. Newton
Dated:  February 6, 2002                                      Title:   Senior Vice President

                               PAGE 10 OF 11 PAGES	

EXHIBIT A
                             JOINT FILING AGREEMENT
                             ----------------------

         John Hancock Financial Services, Inc., John Hancock Life Insurance
Company, John Hancock Subsidiaries LLC, The Berkeley Financial Group, LLC and
John Hancock Advisers, LLC agree that the Terminated Schedule 13G (Amendment No.
1) to which this Agreement is attached, relating to the Common Stock of Wilson
Greatbatch Technologies Inc. is filed on behalf of each of them.

                                                     John Hancock Financial Services, Inc.

                                                     By:      /s/Barry J. Rubenstein
                                                              ----------------------
                                                              Name:    Barry J. Rubenstein
Dated:  February 6, 2002                                      Title:   Vice President, Counsel & Secretary

                                                     John Hancock Life Insurance Company

                                                     By:      /s/Gregory P. Winn
                                                              ------------------
                                                              Name:    Gregory P. Winn
Dated:  February 6, 2002                                      Title:   Vice President & Treasurer

                                                     John Hancock Subsidiaries LLC

                                                     By:      /s/Gregory P. Winn
                                                              ------------------
                                                              Name:    Gregory P. Winn
Dated:  February 6, 2002                                      Title:   Treasurer

                                                     The Berkeley Financial Group, LLC

                                                     By:      /s/Susan S. Newton
                                                              ------------------
                                                              Name:    Susan S. Newton
Dated:  February 6, 2002                                      Title:   Senior Vice President

                                                     John Hancock Advisers, LLC

                                                     By:      /s/Susan S. Newton
                                                              ------------------
                                                              Name:    Susan S. Newton
Dated:  February 6, 2002                                      Title:   Senior Vice President

                               PAGE 11 OF 11 PAGES