--- a/carton.py	Fri Jul 08 15:02:44 2011 -0700
+++ b/carton.py	Fri Jul 08 15:04:15 2011 -0700
@@ -123,7 +123,7 @@
     parser.add_option('-o', dest='outfile',
                       help="specify outfile; otherwise it will come from environment_name")
     parser.add_option('--virtualenv', dest='virtualenv',
-                      help="use virtualenv URL")
+                      help="use this virtualenv URL or file tarball")
     options, args = parser.parse_args(args)
     if len(args) < 2:
         parser.print_usage()