Supplement to the Current Prospectus

Effective  June 1, 2008,  the following  paragraph in the  sub-section  entitled
"Exchange  Privilege"  under the main  heading  "How to  Purchase,  Redeem,  and
Exchange Shares" is deleted in its entirety:

Eligible qualified retirement plans other than Serviced Plans can exchange their
Class R1, Class R2, Class R3, Class R4 and Class R5 shares for shares of the MFS
Money Market Fund. In addition,  Serviced Plans holding Class R3 shares on March
31, 2005,  can exchange their Class R3 shares for shares of the MFS Money Market
Fund.

                  The date of this supplement is June 1, 2008.