I have a Mac user whose dates are messed up. It insists today is Monday November the 10th 2009 but no such date exists! It is the 9th!

The Mac's system time and date are properly set (I've tried both manual settings and sync'd to our ntp server.) Its timezone is also correct.

Needless to say, this is playing havoc with his calendar appts.

Has anyone seen this before? He's running 10.6 with all the latest updates.

I have a Mac running 10.5 and I'm not seeing this problem.