When a editor (non admin) is creating a document inside a protected folder (owned by Admin group) the that document is also owend by the Admin group, this is a problem because the editor can not edit this document after saving. I think that new document created must be owend by the usergroup that created the document.
DImmy
Copiing documents in the same folder does work so for now my client duplicates a document instead of creating a new document.