There is a litter made for cat's that don't like to use their box. It's called Cat Attract...I think. You can find it at Petsmart or whatever. Have you tried that one yet?
And justin....I'm going to pretend you didn't say that!
'He is your friend, your partner, your defender, your dog. You are his life, his love, his leader. He will be yours, faithful and true to the last beat of his heart. You owe it to him to be worthy of such devotion.'-Author Unknown