Windows Vista: Time displayed changes while logging off

I just noticed that when I log off this account (it is non-administrative), after I click “log off” but before it’s finished logging off, the time displayed on the lower right corner of my screen changes. For example, last time the actual time was 9:58 AM, but the display changed to say 7:34. Then when I log back on, the time is back to normal.

Any idea what’s going on here?

I wonder if it’s related to the following strange occurence. When I click on the logo to log onto this account (I haven’t tested with any other accounts) the first time I click, the screen goes blank for a second as though logging on but then just takes me right back to the account selection screen. The second time I click on the logo, it logs in as normal. (However, this latter strange occurence only occurs when the account selection screen has had time to go into screensaver mode. The clock thing, on the other hand, happens every time.)