diff --git a/product/ERP5Type/tests/utils.py b/product/ERP5Type/tests/utils.py
index 8574f8b768801e300b2d31cd16c842f56364cac3..7bb5639bc8c641bfd26364bf01f857b777f9ad3b 100644
--- a/product/ERP5Type/tests/utils.py
+++ b/product/ERP5Type/tests/utils.py
@@ -97,6 +97,10 @@ class DummyMailHostMixin(object):
     cls._previous_message = ()
     cls._message_list = []
 
+  @classmethod
+  def getUid(cls):
+    return 0
+
 class DummyMailHost(DummyMailHostMixin, MailHost):
   pass