We had the same problem with my roommate's dog, Morgan and my cat, Taylor. We just recently started Taylor on something we got from the vet called For-bid which will curb coprophagy and potentially eliminate it completely. Here's a link:
http://www.healthypets.com/forbid.html
We're only 1 week into treatment and while Morgan still goes into my room, she's been less and less likely to eat out of the litter box... Hopefully we can back Taylor off the For-bid in about a week.