Try importing CMFBTreeFolder from CMFCore first.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@5650 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/Document/Folder.py

@@ -39,7 +39,10 @@ from Products.ERP5Type.XMLExportImport import Folder_asXML
 from Products.ERP5Type.Cache import CachingMethod
 from Products.ERP5Type.Utils import sortValueList
 
-from Products.BTreeFolder2.CMFBTreeFolder import CMFBTreeFolder
+try:
+  from Products.CMFCore.CMFBTreeFolder import CMFBTreeFolder
+except ImportError:
+  from Products.BTreeFolder2.CMFBTreeFolder import CMFBTreeFolder
 from AccessControl import getSecurityManager
 from Products.ERP5Type import Permissions