Heh, i love those kind of cats, they suit my personality perfectly :D
Same (kind-of) thing happened to me a while ago CoF, but not as bad.
At college, there is a shop just down the road from the main buildings, which me and my friends often go to in our free periods and our lunchtimes. One time when i went there, we say a fat ginger cat just lazing around on the seats outside the shop, so me and a friend thought how cute it was and went to stroke it. When we approached it, it jumped off the bench, landed on the floor next to our legs, and proceeded to start slashing away at our trousers with its claws!
I now make a wide berth around that cat everytime i see it now