diff --git a/git-am.sh b/git-am.sh
index 876b973a4d..e5af955c6f 100755
--- a/git-am.sh
+++ b/git-am.sh
@@ -131,7 +131,7 @@ do
 		binary=t ;;
 	-3|--3way)
 		threeway=t ;;
-	-s--signoff)
+	-s|--signoff)
 		sign=t ;;
 	-u|--utf8)
 		utf8=t ;; # this is now default