After writting the configuration directly in class-active-directory-employee-list.php, others problems comes.
It seems that a connexion error occurs:
ad-LDAP-extended.php line 101: “Cannot connect LDAP server”
The ramdon_controler function seems to be the problem (for us)(ad-LDAP.php line 2294).
The function is waiting for dc1.something and dc2.something. We are putting here just one element which look like “mls-something”, provided by the sys-admin.