diff --git a/monkeysign/ui.py b/monkeysign/ui.py
index 393db36084b8203ad1d5be588db09943ae498538..a66bc64e2a2b5ed648849bf1f524ee7b4cb84008 100644
--- a/monkeysign/ui.py
+++ b/monkeysign/ui.py
@@ -157,7 +157,7 @@ class MonkeysignArgumentParser(argparse.ArgumentParser):
                                    'passed on the commandline in the "%%(to)s"'
                                    ' field, or the command must parse the '
                                    '"To:" header (default: %(default)s)'))
-        default_mua = "xdg-email --utf8 --to '%%(to)s' --subject '%%(subject)s' --body '%%(body)s' --attach '%%(attach)s'"
+        default_mua = "xdg-email --utf8 --to '%(to)s' --subject '%(subject)s' --body '%(body)s' --attach '%(attach)s'"
         self.add_argument('--mua', nargs='?', default=None, const=default_mua,
                             help=_('Mail User Agent to use to send mail. all '
                                    'parameters are passed on the commandline,'