1 files changed, 1 insertions, 1 deletions
diff --git a/bin/arch b/bin/arch
index 9edf107ca..fd892b484 100644
--- a/bin/arch
+++ b/bin/arch
@@ -25,7 +25,7 @@ from Mailman.Errors import *
 
 try:
     listname, mbox = sys.argv[1:]
-except IndexError:
+except (IndexError, ValueError):
     print "usage: arch <listname> <mbox>"
     sys.exit(0)