Time screwy in Mail

[Thomas Bridgeland]

I am using Mail for e-mail. Recently it has become unreliable. It 
disappears from the Dock at random intervals, and crashes sometimes. 
Also, it does not know the time or date. The time and date displayed on 
the iBook are correct, but on messages I send it is wrong. I just BCCed 
a message and the time was off by four hours in the returned e-mail. In 
the 'Sent' box I checked the e-mail and it showed the correct time. OS 
10.2

Any hints?