oh yea, i know this one! :lol: Biscuit used to do this in exactly the same way. in fact, even when he was at his sickest, he would dra-a-a-ag himself into the bathroom, determined to get to the toilet water.
someone told me it's because the water in toilets is so nice and cold because of the ceramic. when i heard that, i got a nice big ceramic water bowl, but it didn't make a difference.