Wyldkat, do you have a children's hospital nearby? Ours has a bowel clinic equipped with a psychologist who specializes in potty training. For kids over 5, it's apporpriate to seek this kind of help, in case there's a physical reason going on and to get some support for you.
The IEP is based on "educational and functional" needs, not diagnosis; he could qualify under "other health impaired," and it does sound like his participation at school is seriously impaired. In your shoes, I would pursue reopening the case and getting the IEP.
DeeDee
