Class Category Parent Category issue

Hi

We have a hierarchy set  up for a particular  Class Category in R12 that is not behaving as it did in 11i. In 11i the parent class codes were not selectable by users. There is a check box Allow Parent Code Assignment. The check box is read only unless you're setting up a new Class Category. I'd like to update this flag and recompile. Allow Parent Code Assignment is the box I'd like to uncheck to see if that might resolve this issue.

-Marc