Set all private properties to None to prevent unexpected acquisition.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@12084 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5/Document/BusinessTemplate.py

@@ -4883,6 +4883,11 @@ Business Template is a set of definitions, such as skins, portal types and categ
       setattr(self, 'template_portal_type_base_category', ())
       return
 
+# Block acquisition on all _item_name_list properties by setting
+# a default class value to None
+for key in BusinessTemplate._item_name_list:
+  setattr(BusinessTemplate, key, None) 
+
 # Transaction Manager used for update of business template workflow
 # XXX update seems to works without it