If you think that it is not a medical problem that is causing him to do it, go back to potty training him as you did when he was a pup. Don't give him the opportunity to go inside, it seems odd that he would start going in the house after being potty trained for months.
karen, mom to:
ace-gsd (bi-color) 6/14/2010
mandy-yellow lab 1/31/2009
baby-terrier mix (waiting at the bridge)