[imp] IMP and Dovecot Problem

[Servet Guney]

Hi,
We are immigrating our imap/pop servers from UW-Imap to Dovecot.However,we
are experiencing a weird problem.

IMP can not show messages bodies inline with  *"Content-Type:*  text/plain"
when we are using the IMP with Turkish language.However, everthing works
when we choose  another language ( any language is ok from my tries with
different languages).The other message content-types are ok also ( at least
they are being shown as we told to IMP from mime_drivers.).When we set back
with UW-Imap as our imap server everthing works with Turkish Language again.
I am not sure the problem source is either dovecot or IMP.Can anyone give me
a hint or lead to carry on?
Thanks

Our Configuration:

Horde (horde) 3.2-RC2
Posta (imp) H3 (4.2-RC2)
Dovecot 1.1.11

Server:
Debian Linux ( etch )2.6.18-6-amd64 ==> running webserver
Debian Linux (lenny ) 2.6.28.5 ==> running Dovecot
All of the servers have the locale support for ISO-8859-9 and UTF-8 for
turkish

if needed any further information about our configuration.Please ask.I will
supply