diff --git a/product/ERP5CPS/SynchronizationToolPatch.py b/product/ERP5CPS/SynchronizationToolPatch.py
index f85ae3965a3906200743e0ab5cd30f6724c3765e..03b7d3a0f835a4c0c56863b37c2047ee7f40031a 100755
--- a/product/ERP5CPS/SynchronizationToolPatch.py
+++ b/product/ERP5CPS/SynchronizationToolPatch.py
@@ -27,7 +27,10 @@ def editDocument(self, object=None, **kw):
   object._edit(**kw)
   portal_trees = getToolByName(object,'portal_trees')
   for o in portal_trees.objectValues():
-    o.rebuild()
+    try:
+      o.rebuild()
+    except AttributeError,KeyError:
+      pass