Comment 37 for bug 297301

>There are less than 10 (major) IMAP servers
Major doesn't matter, it must work with near all existing and used imap servers. I use for example Hamster as Imap server.

I can not understand why you can not understand this, you must think more global not only for your own point of view.
A user gets a phone call from the sysadmins or a mail a few days ago which tells him : we got a new Imap server software and all Accounts need new passwords, here is your new password, use it tomorrow morning. User opens Thunderbird at the morninbg and thunderbird send x times the wrong password after opening Thunderbird and account is closed.

I agree that there is a UI problem, Thunderbird should tell you why it asks for a new password (The server responded with an error during the login)