I reported a bug about this earlier when we were at version 0.9.6 or so and can't find my bugzilla entry about that anymore. Anyhow: I am using Mozilla 0.9.9 on Win XP and Linux as my mail (2 IMAP accounts) and news client, als well as my default browser. On Windows Mozilla crashes on "Exit", when I have selected "empty Trash on exit" in my mail settings and the IMAP account does not have a "Trash" folder (my second account does not).
dupe of another unconfirmed bug i'll confirm the other one in a sec *** This bug has been marked as a duplicate of 106479 ***
Verified as dup.