I had a problem after refactoring entity objects in Jdev and these blogs helped....
Andrejus Baranovskis' original posting here...
one-size-doesnt-fit-all
After reviewing the suggestions above / thanks guys!! / -- what i ended up doing was looking in my pagedef files and I found an attribute that was not re-factored out. So I remove the culprit and now the error is gone -- good bye~!