diff --git a/lib/python/OFS/ObjectManager.py b/lib/python/OFS/ObjectManager.py
index bbfb28c2ed4181d61f300a01d5699752e8bd95e6..908d1a1592de0bb828bdd939528c33b7d7327e27 100644
--- a/lib/python/OFS/ObjectManager.py
+++ b/lib/python/OFS/ObjectManager.py
@@ -155,6 +155,8 @@ class ObjectManager(
 
     isPrincipiaFolderish=1
 
+    has_order_support = 0 # See OrderSupport.py
+
     def __class_init__(self):
         try:    mt=list(self.meta_types)
         except: mt=[]