diff --git a/moulinette/actionsmap.py b/moulinette/actionsmap.py
index 4458fd44..9d35c24e 100644
--- a/moulinette/actionsmap.py
+++ b/moulinette/actionsmap.py
@@ -526,6 +526,18 @@ class ActionsMap(object):
                     logger.debug('action [%s] executed in %.3fs',
                                  log_id, stop - start)
 
+                    # For some reason we need to do this now before the
+                    # garbage collector kicks in ...
+                    # ... because sometimes the ldap library is already half
+                    # gone when trying to properly close the ldap object
+                    # which leads to  :
+                    # TypeError: "'NoneType' object is not callable" in <bound method Authenticator.__del__ of <moulinette.authenticators.ldap.Authenticator object at 0xabcdef123456>> ignored
+                    # (here the NoneType stuff refers to RequestControlTuples in ldapobject.py ...)
+                    # I got this when running `yunohost user list` (but not when running `yunohost domain list` for some reason)
+                    from moulinette.authenticators.ldap import Authenticator
+                    for i in Authenticator.instances:
+                        i().freecon()
+
     @staticmethod
     def get_namespaces():
         """
diff --git a/moulinette/authenticators/ldap.py b/moulinette/authenticators/ldap.py
index f3625efc..fe83dab9 100644
--- a/moulinette/authenticators/ldap.py
+++ b/moulinette/authenticators/ldap.py
@@ -9,6 +9,7 @@ import crypt
 import ldap
 import ldap.sasl
 import ldap.modlist as modlist
+import weakref
 
 from moulinette.core import MoulinetteError
 from moulinette.authenticators import BaseAuthenticator
@@ -33,11 +34,13 @@ class Authenticator(BaseAuthenticator):
 
     """
 
+    instances = []
     def __init__(self, name, uri, base_dn, user_rdn=None):
         logger.debug("initialize authenticator '%s' with: uri='%s', "
                      "base_dn='%s', user_rdn='%s'", name, uri, base_dn, user_rdn)
         super(Authenticator, self).__init__(name)
 
+        self.__class__.instances.append(weakref.proxy(self))
         self.uri = uri
         self.basedn = base_dn
         if user_rdn:
@@ -52,10 +55,14 @@ class Authenticator(BaseAuthenticator):
             self.authenticate(None)
 
     def __del__(self):
+        self.freecon()
+
+    def freecon(self):
         """Disconnect and free ressources"""
-        if self.con:
+        if self.con and hasattr(self.con, "_l"):
             self.con.unbind_s()
 
+
     # Implement virtual properties
 
     vendor = 'ldap'