diff --git a/product/ERP5/Document/Category.py b/product/ERP5/Document/Category.py
index bde4c659bb5dcb5553e65257317c516bb698d49e..98c5916324823dfa5ea5226de6b0975900ce755b 100644
--- a/product/ERP5/Document/Category.py
+++ b/product/ERP5/Document/Category.py
@@ -112,6 +112,9 @@ class Category(CMFCategory, Predicate, MetaNode, MetaResource):
                       , PropertySheet.Codification
                       , PropertySheet.Reference
                       , PropertySheet.SortIndex)
+
+    # Inheritance
+    __init__ = Predicate.__init__
  
     # Experimental - virtual document access
     def _experimental_aq_dynamic(self, name):