diff --git a/cbc/MME_ConnectionHandler.ttcn b/cbc/MME_ConnectionHandler.ttcn
index ed0502e..4bcc853 100644
--- a/cbc/MME_ConnectionHandler.ttcn
+++ b/cbc/MME_ConnectionHandler.ttcn
@@ -45,6 +45,7 @@
 	void_fn start_fn,
 	CBS_Message exp_cbs_msg optional,
 	SBC_AP_Cause write_replace_warning_ind_cause optional,
+	List_of_TAIs write_repl_unknown_TAIs optional,
 	CellId_Broadcast_List bcast_cell_id_list optional
 };
 
@@ -64,9 +65,16 @@
 function f_sbcap_tx_write_replace_warn_resp(CBS_Message msg, integer idx := 0)
 runs on MME_ConnHdlr {
 	var template (value) SBC_AP_PDU tx;
-	/* TODO: pass Unknown Tracking Area List as parameter above (omit by default) */
-	tx := ts_SBCAP_WRITE_WARNING_RESP(int2bit(msg.msg_id, 16),
-					  int2bit(msg.ser_nr, 16));
+	if (ispresent(g_pars.write_repl_unknown_TAIs)) {
+		tx := ts_SBCAP_WRITE_WARNING_RESP_UNKNOWN_TAI(
+						int2bit(msg.msg_id, 16),
+						int2bit(msg.ser_nr, 16),
+						SBC_AP_Cause_message_accepted,
+						g_pars.write_repl_unknown_TAIs);
+	} else {
+		tx := ts_SBCAP_WRITE_WARNING_RESP(int2bit(msg.msg_id, 16),
+						  int2bit(msg.ser_nr, 16));
+	}
 	f_SBC_AP_send(tx, idx);
 }