Sounds like a bad flash to me too, like Omardeth stated. This board probably doesn't have this, but you could check to see if there's a reset CMOS jumper on you board. You might also remove the battery for the afternoon to try to reset the bios. If any of this doesn't work, you have a couple of options.
1 )Contact the mobo manufacturer and see if they will send/sell you a new bios chip with the rev. you wanted. I don't know what they will charge for this.
2) Head over to
www.badflash.com and purchase a new bios chip.
Mike
EDIT: I also don't like to flash my bios unless there's a feature I really need and there's no other way to get it. I recently flashed my EpOX board to get it to support a new faster processor that I wanted to purchase.