Mao- Get your cat to a vet right away! I don't know about the pooping, but drinking lots of water and excessive urinating is a STRONG sign of kidney problems....either failure or cancer or something. I know what I am talking about, because my cat (Liza) died last year from it. She was 12 years old and starting drinking a lot of water and going pee way more than normal. I did not know that it was a 'sign' of problems until it was too late. At first she seemed to feel fine, and by the time she acted sick it was too late. I felt sooooo horrible and guilty. I am sorry to scare you, and I hope it is not the case with your cat, but odds are, that there is definately something going on with the kidneys. Go to the vet right away, and good luck. Please let us know how things go.