diff --git a/swiftclient/shell.py b/swiftclient/shell.py
index 15ca5706..f7c24762 100755
--- a/swiftclient/shell.py
+++ b/swiftclient/shell.py
@@ -1416,6 +1416,7 @@ Examples:
         logging.getLogger("swiftclient")
         if options.debug:
             logging.basicConfig(level=logging.DEBUG)
+            logging.getLogger('iso8601').setLevel(logging.WARNING)
         elif options.info:
             logging.basicConfig(level=logging.INFO)