diff --git a/addons/base_action_rule/base_action_rule.py b/addons/base_action_rule/base_action_rule.py
index 98d533b3b6d..398bf00286a 100644
--- a/addons/base_action_rule/base_action_rule.py
+++ b/addons/base_action_rule/base_action_rule.py
@@ -199,7 +199,7 @@ class base_action_rule(osv.osv):
         for action_rule in self.browse(cr, SUPERUSER_ID, ids):
             model = action_rule.model_id.model
             model_obj = self.pool.get(model)
-            if not hasattr(model_obj, 'base_action_ruled'):
+            if model_obj and not hasattr(model_obj, 'base_action_ruled'):
                 model_obj.create = self._wrap_create(model_obj.create, model)
                 model_obj.write = self._wrap_write(model_obj.write, model)
                 model_obj.base_action_ruled = True