diff --git a/ldap_locks.py b/ldap_locks.py
index 8494de6..60ab19a 100644
--- a/ldap_locks.py
+++ b/ldap_locks.py
@@ -39,7 +39,6 @@ import exceptions
 import socket
 import crans_utils
 import collections
-import subprocess
 import time
 
 class LockError(exceptions.StandardError):
@@ -87,14 +86,14 @@ class LdapLockHolder:
         l'objet.
         """
         if Id == None:
-            for key, subdict in self.locks['default'].keys():
+            for key, subdict in self.locks['default'].iteritems():
                 for item, value in subdict:
                     try:
                         self.removelock(item, value, key)
                     except:
                         pass
         else:
-            for item, value in self.locks[Id].items():
+            for item, value in self.locks[Id].iteritems():
                 try:
                     self.removelock(item, value, Id)
                 except: