diff --git a/knowledge/interfaces.py b/knowledge/interfaces.py
index 0c89a1b..0a214fa 100644
--- a/knowledge/interfaces.py
+++ b/knowledge/interfaces.py
@@ -1,5 +1,5 @@
 #
-#  Copyright (c) 2007 Helmut Merz helmutm@cy55.de
+#  Copyright (c) 2008 Helmut Merz helmutm@cy55.de
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by
@@ -43,7 +43,7 @@ class IPerson(IBasePerson, IKnowing):
     """
 
 
-class ITask(IBaseTask, IRequirementProfile):
+class ITask(IConceptSchema, IBaseTask, IRequirementProfile):
     """ A task, also acting as a knowledge requirement profile.
     """