SECTION 906 CERTIFICATION

Pursuant to 18 U.S.C.ss.  1350, the undersigned  officers of Federated Municipal
Securities  Income Trust on behalf of:  Federated  California  Municipal  Income
Fund,  Federated  Michigan  Intermediate  Municipal  Trust,  Federated  New York
Municipal Income Fund, Federated North Carolina Municipal Income Fund, Federated
Ohio  Municipal  Income  Fund,  Federated  Pennsylvania  Municipal  Income Fund,
Federated Vermont Municipal Income Fund (the  "Registrant"),  hereby certify, to
the best of our knowledge,  that the  Registrant's  Report on Form N-CSR for the
period  ended  February  28,  2005  (the  "Report")   fully  complies  with  the
requirements  of Section 13(a) or 15(d),  as  applicable,  of the Securities and
Exchange Act of 1934 and that the  information  contained  in the Report  fairly
presents,  in all material  respects,  the  financial  condition  and results of
operations of the Registrant.


Dated: April 19, 2005

/s/ J. Christopher Donahue

Title: President, Principal Executive Officer



Dated: April 19, 2005

/s/ Richard J. Thomas

Title: Treasurer, Principal Financial Officer

This  certification is being furnished solely pursuant to 18 U.S.C.ss.  1350 and
is not being filed as part of the Report or as a separate disclosure document.