diff --git a/addons/users_ldap/users_ldap.py b/addons/users_ldap/users_ldap.py
index e4615907c79..0846bb408f6 100644
--- a/addons/users_ldap/users_ldap.py
+++ b/addons/users_ldap/users_ldap.py
@@ -180,7 +180,7 @@ class CompanyLDAP(osv.osv):
         """
         
         user_id = False
-        login = tools.ustr(login)
+        login = tools.ustr(login.lower())
         cr.execute("SELECT id, active FROM res_users WHERE login=%s", (login,))
         res = cr.fetchone()
         if res: