It was my own problem with some files in ~/.compiz/session/. Now I have solved and it works fine.
Excuse me if I report a false bug! I think you can close here. Cheers! Filippo :) -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org