--- a/ClassDescription.st	Fri Feb 26 19:48:26 2016 +0100
+++ b/ClassDescription.st	Fri Feb 26 20:48:29 2016 +0100
@@ -1116,9 +1116,9 @@
 !
 
 nameSpace
-    "raise an error: must be redefined in concrete subclass(es)"
-
-    ^ self subclassResponsibility
+    "should be redefined in concrete subclass(es)"
+
+    ^ nil
 !
 
 renameCategory:oldCategory to:newCategory