User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.5) Gecko/20091105 Fedora/3.5.5-1.fc11 Firefox/3.5.5 Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.4pre) Gecko/20091014 Fedora/3.0-2.8.b4.fc11 Thunderbird/3.0b4 Randomly, email in my folders, sometimes years old, will be marked as unread. Sometimes the email will be set "marked for deletion". I can click on the folders or emails to "unmark for deletion" or "mark as read" as need be. I can also "rebuild index" of the folder and that fixes everything. I'm using dovecot 1.2.8 and old versions of Thunderbird and current versions of Kmail, Alpine, and MS Outlook seem to work absolutely fine with it. It's the version 3 line of Thunderbird products that are the problem. This is very annoying, and the fact that it marks messages for deletion is a huge problem -- I don't want to loose any mail. I'm switching back to TB 2, in the meantime. Reproducible: Sometimes Steps to Reproduce: This happens randomly. I could step away from my computer and when I come back it could've happened. I suppose it happens when Thunderbird queries the IMAP server.

There's a 3.01 + bug fix linux build here that will probably fix the issue: http://s3.mozillamessaging.com/build/try-server/2010-01-20_15:30-bienvenu@nventure.com-1264029848/bienvenu@nventure.com-1264029848-mail-try-linux.tar.bz2 or you could set mail.server.default.use_condstore to false.