diff --git a/product/ERP5/Tool/InterpolationTool.py b/product/ERP5/Tool/InterpolationTool.py
index 88ba59f8154a9894623130f10df7faa326188a59..617a7d28b6f4680c779f0ed414283ded0c3ddaed 100644
--- a/product/ERP5/Tool/InterpolationTool.py
+++ b/product/ERP5/Tool/InterpolationTool.py
@@ -34,6 +34,9 @@ from DateTime import DateTime
 
 from zLOG import LOG
 
+from Products.ZSQLCatalog.ZSQLCatalog import ZCatalog
+from Products.CMFCore.CatalogTool import CatalogTool as CMFCoreCatalogTool
+
 class InterpolationTool (UniqueObject):
     """
     The InterpolationTool centralises interpolation
@@ -71,6 +74,9 @@ class InterpolationTool (UniqueObject):
 
     # Explicite Inheritance
     _listAllowedRolesAndUsers = CMFCoreCatalogTool._listAllowedRolesAndUsers
-    __url = CMFCoreCatalogTool.__url
+
+    # XXX does not work fix me
+    # AttributeError: type object 'CatalogTool' has no attribute '_InterpolationTool__url'
+    #__url = CMFCoreCatalogTool.__url
 
 InitializeClass(InterpolationTool)