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MFS(R) MUNICIPAL INCOME FUND
Supplement to the Current Prospectus
The description of portfolio manager under the "Management of the Fund
Investment Adviser" section is hereby revised as follows: Effective March 4,
1998, John P. Kihn is the portfolio manager of the Fund. Mr. Kihn, a Vice
President of the Adviser, has been employed as a portfolio manager with the
Adviser since October, 1997. From 1996 to 1997, he worked as a Senior
Quantitative Analyst and Vice President of Putnam Investment Management, Inc.;
from 1992 to 1996, he attended the London School of Economics where he was
awarded a doctorate in Finance; and from 1994 to 1995, he was an associate
portfolio manager with Colonial Management Associates, Inc.
The date of this Supplement is March 4, 1998.
