diff --git a/cts/agents/cpg_test_agent.c b/cts/agents/cpg_test_agent.c
index 608e1340..e15748cf 100644
--- a/cts/agents/cpg_test_agent.c
+++ b/cts/agents/cpg_test_agent.c
@@ -487,7 +487,7 @@ static void send_some_more_messages_normal (void)
 static void send_some_more_messages (void * unused)
 {
 	if (use_zcb) {
-//		send_some_more_messages_zcb ();
+		send_some_more_messages_zcb ();
 	} else {
 		send_some_more_messages_normal ();
 	}