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VERTEX ALL CAP FUND
Supplement to the Current Prospectus
The description of portfolio managers under the "Management of the Funds"
section is hereby restated as follows:
John W. Ballen, President and Chief Investment Officer of MFS, has been employed
by MFS as a portfolio manager since 1984. Mr. Ballen has been the fund's
portfolio manager since March 1999. Toni Y. Shimura, a Senior Vice President of
MFS, has been employed by MFS as a portfolio manager since 1987. Ms. Shimura
became a portfolio manager of the fund on February 1, 2000.
The date of this Supplement is February 1, 2000.
