Is there any way to have an iPad auto update its date and time?
It should update automatically by default (Settings &rarr; General &rarr; Date &amp; Time).

Are you running the latest iPad OS (3.2.2)? I have a vague recollection of a bug in the iPad that caused the time to go out of sync that might have been fixed in a software update. I can't seem to find any info about it, but you might want to update the software just in case.