Oh sorry, you are right. Everything is ok.
So the pb was the configuration file /etc/apache2/mods-available/debian-edu-userdir.conf.
I've two tjener: one at home for tests, and one at work.
I test at work with tt (a normal user), but at home, I 've tested with my first user (big mistake).
Sorry.
Eveything is ok now.
Thanks everybody !!