seems a block at height 74638 has expoited a bug in the net. It uses an integer overflow to make a negative total transaction. The two transaction outputs are:
out Value:92233720368.54(7ffffffffff85ee0) out Value:92233720368.54(7ff ffffffff85ee0)
We need a fix asap
Edit: (satoshi) 0.3.10 patch download links here: http://bitcointalk.org/index.php?topic=827.0