I have more information on this bug. It seems to be caused by a problem with the imap implementation. When using pop3 the e-mails are displayed fine. Other mail readers do not have trouble displaying these messages.
Nice detail: The imap server causing these troubles is a Novell one. -- Non-text attachments are shown inline as if they are text https://launchpad.net/bugs/59140 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs