I can not find a way to edit description so I write it as a comment. I hope it is not a problem.

Problematic situation is when we have two entities in one to many relation (Task and Note in this case). The "parent" of the relation has to be annotated with cascade PERSIST and the returned type has to be a map. When the element of that map is retrieved and passed to the entity manager remove method, the removal does not take place.

I really apologize for not adding description. In my opinion example/test case is more descriptive than my poor English.

If you have any more question/suggestions feel free to ask.