diff --git a/refpolicy/doc/templates/interface.html b/refpolicy/doc/templates/interface.html
index 0a96a11d..d9c68839 100644
--- a/refpolicy/doc/templates/interface.html
+++ b/refpolicy/doc/templates/interface.html
@@ -9,11 +9,11 @@
 			,
 		[[end]]
 		[[exec i = 1]]
-		[[if arg['optional'] == 'true']]
+		[[if arg['optional'] == 'yes']]
 			[
 		[[end]]
 		[[arg['name']]]
-		[[if arg['optional'] == 'true']]
+		[[if arg['optional'] == 'yes']]
 			]
 		[[end]]
 	[[end]]