In EAR project properties (Packaging - I hope it's correct way to remove child
modules) remove modules. ProjectEar.getChildModuleProviders() still returns all
of them. 
Can be easy reproduced with Call EJB dialog:
1. create Enterprise app wit EJB and Web module
2. create new Session bean with local interface
3. create new servlet
4. in servlet's code invoke Call Enterprise Bean action, you can select Session
bean and OK button is enabled.
5. Cancel dialog
6. In properties/packaging of application remove all modules
7. Invoke Call EJB in servlet once again, you can still select Session bean and
have enabled OK button
8. Restart IDE and try Call EJB from servlet once again, now everything is OK