Edit: Tried more things without success, started a thread about it: http://forum.bitcoin.org/index.php?topic=18773.0
I have a weird uncomfirmed transaction as well: http://blockexplorer.com/t/8e8M6K4QqW
It's in a block. I've sent a few bitcents to the address from both the wallet that contains the address and another one, and both transactions confirm as normal. I have cleared out the appdata folder and had the client download the blockchain again. So far, still unconfirmed.
Right now I'm running bitcoind with -rescan to see if that does something.
Unless that works, I'm going to assume that block#131313 is indeed bad luck three times over.