diff --git a/lib/layouts/amsdefs.inc b/lib/layouts/amsdefs.inc
index 993bd4777a..c6425607e0 100644
--- a/lib/layouts/amsdefs.inc
+++ b/lib/layouts/amsdefs.inc
@@ -70,6 +70,7 @@ Style Title
 	Align                 Center
 	AlignPossible         Center
 	LabelType             No_Label
+	OptionalArgs          1
 	Font
 	  Shape               Smallcaps
 	  Series              Bold