Apple Mail losing all state

Seen this scenario a couple of times:

1. Mac crashes
2. Reboot and when Mail starts up, it's lost all of it's state and wants me to re-enter all my accounts information.

Fortunately, all my email is in IMap, so it's just a matter of restoring Mail's state about my IMap accounts. This is done by shutting down Mail, replacing ~/Library/Preferences/com.apple.mail.plist with a good copy from a backup.