Message contains invalid header

[Marten Lehmann]

Hello,

> But your Cyrus IMAPd has to work with these headers! It has to be able
> to sort by date, search for message ID, index the body, search for any
> header field! So you cannot just ignore errors in Cyrus.

yes, I understand. But I don't know which characters are problematic for 
Cyrus. I just see the message "Message containes invalid headers". So 
what? Is it an empty Message-ID? Is it a NUL-character? Is it 8bit in 
header where usually only 7bit is allowed (munge8bit is false in our 
setup)? There is now documentation on this. Do I have to be a programmer 
in watch through thousand lines of source code to find it out? Actually, 
I just want to use Cyrus, not change it.

Regards
Marten