I am actually having the same problem. Every so often one, two or three of my clients freeze up. The others still work and you can even see the frozen client's toons still moving around and doing whatever. I disabled the catalyst AI thingy and that helped a bit but still having problems. If I exit one of the other unfrozen clients the others magically work again.

The other day I was logging off wow and had such bad lag I just hit the power button. Afterwards i started getting those horribly fatal #134 errors so i ended up reinstalling windows and wow. Ever since then I have been having all kinds of problems. i installed warcraft and bc from disk and downloaded the lich from bizz. i'm wondering if that download got corrupted. used repair and deleted some of the mpqs as i found in a blue posting..did another repair. fatal crashes stopped but the weird freezing continues.