diff --git a/product/ERP5Type/Utils.py b/product/ERP5Type/Utils.py
index 1bcb22da5562c14c5ab7311e5a31673dc6ac686b..2ef40914a6f19559e9a03ee7338478ec1a6d84a7 100644
--- a/product/ERP5Type/Utils.py
+++ b/product/ERP5Type/Utils.py
@@ -999,10 +999,13 @@ def setDefaultConstructor(klass):
       document_constructor.__name__ = document_constructor_name
 
 
-def createExpressionContext(object, portal):
+def createExpressionContext(object, portal=None):
   """
     Return a context used for evaluating a TALES expression.
   """
+  if portal is None and object is not None:
+    portal = object.getPortalObject()
+
   if object is None or getattr(object, 'aq_base', None) is None:
     folder = portal
   else: