Special characters are displayed as question mark (?)

[wiscalico]

Hi.

I have a current email setup using Postfix 2.1 and Courier-IMAP 3.0.3 with a MySQL backend for users. I have migrated email to a Open Source Edition of Zimbra 4.5.9. The subject and sender when containing special chars like æøå is replaced by a question mark (?) but only on some of the emails when viewing them with Thunderbird or Evolution through IMAP. When using the Zimbra web interface there is no problem.

The same emails back on my old system is displayed correct in Thunderbird and Evolution. I have tried to move emails both with imapsync and by exporting / importing in Thunderbird. As soon as the email is on the Zimbra system the characters is displayed as ?

Have anyone experienced the same or even better does anyone know how to fix this. I fear this is not a problem caused by the migration.

The weird thing is that it is only displayed wrong in the list of emails in a folder and not on the email it self. I have attached a screenshot of the "problem".