diff --git a/hnodeb/HNB_Tests.ttcn b/hnodeb/HNB_Tests.ttcn
index a58e203..24feab8 100644
--- a/hnodeb/HNB_Tests.ttcn
+++ b/hnodeb/HNB_Tests.ttcn
@@ -174,10 +174,10 @@
 function f_start_handler(void_fn fn, template (omit) TestHdlrParams pars_tmpl := omit)
 runs on test_CT return HNBGW_ConnHdlr {
 	var TestHdlrParams pars;
-	if (isvalue(pars)) {
-		pars := valueof(pars_tmpl);
-	} else {
+	if (istemplatekind(pars_tmpl, "omit")) {
 		pars := valueof(f_gen_test_hdlr_pars());
+	} else {
+		pars := valueof(pars_tmpl);
 	}
 	return f_start_handler_run(f_start_handler_create(pars), fn, pars);
 }