--- demo.py	2007-10-05 05:06:21.000000000 +0200
+++ demo.py.modified	2009-01-19 01:12:43.000000000 +0100
@@ -108,7 +108,7 @@
 run demo on a server host, please stop the demo, open file
 "demo/config.ini" with your editor, change the host name in the "web"
 option in section "[tracker]", save the file, then re-run the demo
-program.
+program. If you want to change backend types, you must use "nuke".
 
 ''' % url
 
@@ -122,11 +122,17 @@
     Sets up the web service on localhost. Disables nosy lists.
     """
     home = os.path.abspath('demo')
-    if not os.path.exists(home) or (sys.argv[-1] == 'nuke'):
-        if len(sys.argv) > 2:
-            backend = sys.argv[-2]
-        else:
-            backend = 'anydbm'
+    backend = 'anydbm'
+    try:
+        backend = sys.argv[1]
+    except:
+        pass
+    nuke = False
+    try:
+        nuke = sys.argv[2] == 'nuke'
+    except:
+        pass
+    if not os.path.exists(home) or nuke:
         install_demo(home, backend, os.path.join('templates', 'classic'))
     run_demo(home)