diff --git a/openerp/addons/base/res/res_users.py b/openerp/addons/base/res/res_users.py
index 68676035d02..e5c24bb7b19 100644
--- a/openerp/addons/base/res/res_users.py
+++ b/openerp/addons/base/res/res_users.py
@@ -32,6 +32,7 @@ from openerp import SUPERUSER_ID, models
 from openerp import tools
 import openerp.exceptions
 from openerp.osv import fields, osv, expression
+from openerp.service.security import check_super
 from openerp.tools.translate import _
 from openerp.http import request
 
@@ -426,10 +427,7 @@ class res_users(osv.osv):
         return dataobj.browse(cr, uid, data_id, context=context).res_id
 
     def check_super(self, passwd):
-        if passwd == tools.config['admin_passwd']:
-            return True
-        else:
-            raise openerp.exceptions.AccessDenied()
+        return check_super(passwd)
 
     def check_credentials(self, cr, uid, password):
         """ Override this method to plug additional authentication methods"""
diff --git a/openerp/service/security.py b/openerp/service/security.py
index a5d392e7c0d..373b845051f 100644
--- a/openerp/service/security.py
+++ b/openerp/service/security.py
@@ -27,10 +27,9 @@ def login(db, login, password):
     return res_users._login(db, login, password)
 
 def check_super(passwd):
-    if passwd == openerp.tools.config['admin_passwd']:
+    if passwd and passwd == openerp.tools.config['admin_passwd']:
         return True
-    else:
-        raise openerp.exceptions.AccessDenied()
+    raise openerp.exceptions.AccessDenied()
 
 def check(db, uid, passwd):
     res_users = openerp.registry(db)['res.users']