10.2.4 and Mail - losing settings

Installed 10.2.4 on the day it was available via software update, found an odd problem. My email broke, the updater reset the .Mac account settings in the Internet control panel. So when I ran Mail it had disabled my .mac account. No where in the Mail application does it suggest that this is the issue. Your .mac account is disabled and you can't enable it, you can't edit the username, so you can't save the account. After a few tries of this and a session of repair permissions I remembered the preference setting for .Mac in the System Preferences.
It shouldn't be this hard to fix this. Also when an account is inactive you cannot access the folders of stored email, so suddenly my email vanished. not fun, though all is now better.