diff --git a/rs.spec b/rs.spec
index b7eaed1..74445d3 100644
--- a/rs.spec
+++ b/rs.spec
@@ -19,6 +19,7 @@
 AssignName {
 	param void *obj
 	param const char *name
+	param size_t len
 	}
 
 ElementBegin {