JOHN HANCOCK SERIES TRUST 101 Huntington Avenue Boston, MA 02199 John Hancock Funds, Inc. 101 Huntington Avenue Boston, MA 02199 Ladies and Gentlemen: Pursuant to Section 14 of the Distribution Agreement dated as of December 2, 1996 between John...

                            XXXX XXXXXXX SERIES TRUST
                              000 Xxxxxxxxxx Xxxxxx
                                Xxxxxx, XX 00000



Xxxx Xxxxxxx Funds, Inc.
000 Xxxxxxxxxx Xxxxxx
Xxxxxx, XX  00000

Ladies and Gentlemen:

         Pursuant  to  Section  14 of the  Distribution  Agreement  dated  as of
December 2, 1996  between  Xxxx  Xxxxxxx  Series  Trust (the  "Trust")  and Xxxx
Xxxxxxx  Funds,  Inc.,  please be advised that the Trust has  established  a new
series of its shares,  namely,  Xxxx  Xxxxxxx 500 Index Fund (the  "Fund"),  and
please be further  advised that the Trust desires to retain Xxxx Xxxxxxx  Funds,
Inc. to serve as distributor and principal  underwriter  under the  Distribution
Agreement for the Fund.

         Please indicate your acceptance of this  responsibility by signing this
letter as indicated below.



XXXX XXXXXXX FUNDS, INC.            XXXX XXXXXXX SERIES TRUST



By: /s/ Xxxxx X. Xxxxxxx            By:  /s/Xxxx X. Xxxxxxx
    --------------------                 ------------------
        Xxxxx X. Xxxxxxx                 Xxxx X. Xxxxxxx
        President                        President


Dated:  August 18, 1999


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