It might be misreading your "null" as a negative number - epoch time is measured as the number of seconds from 1.1.1970 IIRC, and a lot of time values are stored in the database in epoch time values. I'd check the code but I'M ON VACATION! so maybe Aaron'll get bored later today and tell you.
I'm just glad it finally made the cut! Yeah, I guess I've been more of a lurker over the past year or so (or more), but I've been an avid lurker. (Mostly I've just been waiting for another year of logo submissions!)