We recently purchased a used log cabin to use as a guest house. We didn't notice at the time of purchase that something had been sprayed (some sort of a dark stain) all over the interior walls and then varnished over. We tried sanding it off to no avail, as the varnish just gummed up the sand paper. We are now using Jasco environmentally friendly stripper - but this is a sticky horrible HUGE job. Is there any other way to get this stain off the walls? It has been varnished in. UGH! HELP!