diff -up system-config-printer-1.1.16/monitor.py.check-still-connecting system-config-printer-1.1.16/monitor.py
--- system-config-printer-1.1.16/monitor.py.check-still-connecting	2009-12-22 14:44:19.000000000 +0000
+++ system-config-printer-1.1.16/monitor.py	2010-01-18 16:31:05.664560326 +0000
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 
-## Copyright (C) 2007, 2008, 2009 Tim Waugh <twaugh@redhat.com>
-## Copyright (C) 2007, 2008, 2009 Red Hat, Inc.
+## Copyright (C) 2007, 2008, 2009, 2010 Red Hat, Inc.
+## Author: Tim Waugh <twaugh@redhat.com>
 
 ## 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
@@ -208,7 +208,9 @@ class Monitor:
             self.connecting_timers[printer] = timer
             return False
 
-        del self.connecting_timers[printer]
+        if self.connecting_timers.has_key (printer):
+            del self.connecting_timers[printer]
+
         debugprint ("Still-connecting timer fired for `%s'" % printer)
         (printer_jobs, my_printers) = self.sort_jobs_by_printer ()
         self.update_connecting_devices (printer_jobs)