diff --git a/bsc/BSC_Tests.ttcn b/bsc/BSC_Tests.ttcn
index dee41d2..24df03f 100644
--- a/bsc/BSC_Tests.ttcn
+++ b/bsc/BSC_Tests.ttcn
@@ -1511,6 +1511,27 @@
 }
 
 
+/* 24.008 8.4 Unknown message must trigger RR STATUS */
+private function f_tc_err_84_unknown_msg(charstring id) runs on MSC_ConnHdlr {
+	f_est_single_l3(ts_RRM_UL_REL('00'O));
+	timer T := 3.0
+	alt {
+	[] RSL.receive(tr_RSL_DATA_REQ(g_chan_nr, ?, decmatch tr_RRM_RR_STATUS)) {
+		setverdict(pass);
+		}
+	[] BSSAP.receive { setverdict(fail, "unexpected BSSAP"); }
+	[] T.timeout { setverdict(inconc); }
+	}
+}
+testcase TC_err_84_unknown_msg() runs on test_CT {
+	var MSC_ConnHdlr vc_conn;
+	f_init(1, true);
+	f_sleep(1.0);
+	vc_conn := f_start_handler(refers(f_tc_err_84_unknown_msg), testcasename());
+	vc_conn.done;
+}
+
+
 
 control {
 	/* CTRL interface testing */
@@ -1579,6 +1600,7 @@
 	execute( TC_unsol_ass_compl() );
 	execute( TC_unsol_ho_fail() );
 	execute( TC_err_82_short_msg() );
+	execute( TC_err_84_unknown_msg() );
 }
 
 }