I hope this is the right area to post this.
My little Leo is 19 weeks and pee pad trained. We were doing really, really good. He was going potty on his own and hadn't had an accident in a few weeks. My parents where here for a few days and my Dad even comminted on how well Leo was doing on his potty training. We even trust him to be out all night in our youngest DD' room.
Then 2 weeks ago he started putting his front paws and one back paw on the potty pad and would pee with one leg up. Last week, he would put his front paws on to the pee pad (in the litter box) and leave his back paws on the ground & pee.
As you can guess... the pee goes all over the floor. 
I have tried everything I can think of to stop him and nothing is working. The first few times, I would yell to get his attention. He would just continue to pee...while he looked at me. I tried putting the potty pad on the floor. If it was on the floor he would pee on the edge & all over the floor. I tried putting a potty pad upside down in front of the litter box. So it would have a different dexture. He would still climb into the litter box, with only his front paws and pee...on the floor.
By Friday he had peed on the floor all day long and I was so frustated I was in tears! Saturday, I put a bathroom rug in front of the litter box. He was is still putting only his front paws in.
**I am now starting potty training all over again. I am have him on a leash (like when we first came home)and he goes every where I go, I take him potty every few hours, I give him a treat if he goes potty correctly.
Has anyone had this problem? What do you guys think? Any suggestions?