The only folks who have that problem are the ones with Sony Readers, nathantw.
It's a known bug, apparently the Reader uses a counter to keep track of the date, and when it hits a certain size it overflows and resets back to that date in '06.
At least with the 505 there's a place in the menus to set the stupid date on the device itself, those of us with 500's have to connect back to a computer and get the eBook Library to do it
for us.