Shareholder Proxy Services
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September 15, 2009
IMPORTANT MATTER
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Re: Pioneer Municipal High Income Trust (NYSE: MHI)
Cusip: 723763108
Dear Shareholder:
Our firm has been retained by Pioneer Municipal High Income Trust to contact you
regarding your investment in common shares of the Trust, as of record date
July 9, 2009. We have attempted to contact you, but have yet to be successful.
Please contact us immediately at 1-800-232-1064 between the hours of
9:00 a.m. and 11:00 p.m., Eastern Standard Time.
Thank you in advance for your assistance with this matter.
Sincerely,
PFred Bonnell
Investor Relations Supervisor
Shareholder Services
The Altman Group
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60 East 42nd Street, New York, New York 10165