I've got this in another thread, but I think I could mention it here too.
http://goallineblitz.com/game/replay.pl?game_id=300353&pbp_id=1579643Fingas, I've seen that non-sack call before. From what I understand, he wasn't awarded a sack because it was a designed QB run. QB gets treated like a regular RB on that play for sack purposes. Why Big Sack kicked in for that, I don't know.