As project admin, when I try to select a user group to bind it to project members, I always get an alert "Directory group custom_ugroup_ldap does not exist." It is in fact a 500 error due to a PHP fatal error in bind_members_confirm.php
Fatal error: Class 'LDAP_GroupManager' not found in /usr/share/tuleap/plugins/ldap/include/LDAP_ProjectGroupManager.class.php on line 29