diff --git a/swig/Lasso-wsf.i b/swig/Lasso-wsf.i
index b7d7d401..c97ea156 100644
--- a/swig/Lasso-wsf.i
+++ b/swig/Lasso-wsf.i
@@ -273,7 +273,7 @@ typedef struct {
 	END_THROW_ERROR
 
 	THROW_ERROR
-	int initQuery(const char *security_mech_id);
+	int initQuery(const char *security_mech_id = NULL);
 	END_THROW_ERROR
 
 	THROW_ERROR