diff --git a/cbc/CBC_Tests.ttcn b/cbc/CBC_Tests.ttcn
index 406baed..9beaddf 100644
--- a/cbc/CBC_Tests.ttcn
+++ b/cbc/CBC_Tests.ttcn
@@ -160,6 +160,7 @@
 		start_fn := refers(f_MME_ConnHdlr_start_fn_void),
 		exp_cbs_msg := omit,
 		write_replace_warning_ind_cause := omit,
+		write_repl_unknown_TAIs := omit,
 		bcast_cell_id_list := omit
 	};
 	return pars;
@@ -498,6 +499,25 @@
 	f_shutdown_helper();
 }
 
+/* Create and delete message with MME available. MME reports
+ * Write-Replace-Response with Unknown TAI IE.
+ */
+testcase TC_ecbe_create_delete_mme_unknown_tai() runs on test_CT {
+	var template (value) List_of_TAIs write_repl_unknown_TAIs;
+	var template (value) CBS_Message msg := t_CBSmsg(48, 16752);
+
+	f_init(num_bsc := 0, num_mme := 1);
+
+	write_repl_unknown_TAIs := {{ts_SBCAP_TAI(f_enc_mcc_mnc('901'H, '70'H), 1234)}};
+	g_pars_MME[0].start_fn := refers(f_mme_create_and_delete);
+	g_pars_MME[0].exp_cbs_msg := valueof(msg);
+	g_pars_MME[0].write_replace_warning_ind_cause := SBC_AP_Cause_message_accepted;
+	g_pars_MME[0].write_repl_unknown_TAIs := valueof(write_repl_unknown_TAIs);
+	f_start();
+	f_create_and_delete(valueof(msg));
+	f_shutdown_helper();
+}
+
 /* Create and delete message with both BSC and MME available */
 testcase TC_ecbe_create_delete_bsc_and_mme() runs on test_CT {
 	f_init(num_bsc := 1, num_mme := 1);
@@ -585,6 +605,7 @@
 	execute( TC_ecbe_create_delete_ci() );
 	execute( TC_ecbe_create_delete_lai() );
 	execute( TC_ecbe_create_delete_mme_indication() );
+	execute( TC_ecbe_create_delete_mme_unknown_tai() );
 	execute( TC_ecbe_create_delete_bsc_and_mme() );
 	execute( TC_ecbe_create_delete_bsc_server() );
 	execute( TC_ecbe_create_delete_mme_server() );