Index: /home/sebp/workspace/deskbar-applet-2.20/deskbar/core/DeskbarHistory.py
===================================================================
--- /home/sebp/workspace/deskbar-applet-2.20/deskbar/core/DeskbarHistory.py	(revision 1738)
+++ /home/sebp/workspace/deskbar-applet-2.20/deskbar/core/DeskbarHistory.py	(working copy)
@@ -168,6 +168,8 @@
         if action.skip_history():
             self.reset()
             return
+        if text == None or action == None:
+            raise Exception, "tried to add None value to history. text: %s, action: %s" % (text, action)
         
         for idx, val in enumerate(self):
             htime, htext, haction = val
