diff --git a/msc/MSC_Tests.ttcn b/msc/MSC_Tests.ttcn
index 517afe0..daadc2b 100644
--- a/msc/MSC_Tests.ttcn
+++ b/msc/MSC_Tests.ttcn
@@ -1444,7 +1444,11 @@
 	var PDU_ML3_MS_NW l3_lu := f_build_lu_imsi(g_pars.imsi);
 	f_create_gsup_expect(hex2str(g_pars.imsi));
 	f_bssap_compl_l3(l3_lu);
-	BSSAP.send(ts_BSSMAP_ClassmarkUpd(g_pars.cm2, g_pars.cm3));
+	if (pars.send_early_cm) {
+		BSSAP.send(ts_BSSMAP_ClassmarkUpd(g_pars.cm2, g_pars.cm3));
+	} else {
+		pars.cm1.esind := '0'B;
+	}
 	f_mm_auth();
 	alt {
 	[] BSSAP.receive(tr_PDU_DTAP_MT(tr_ML3_MT_LU_Rej)) { }
@@ -1465,7 +1469,19 @@
 	f_vty_config(MSCVTY, "network", "authentication required");
 	f_vty_config(MSCVTY, "network", "encryption a5 3");
 
-	vc_conn := f_start_handler(refers(f_tc_lu_imsi_auth_tmsi_encr_3_1), 36);
+	vc_conn := f_start_handler(refers(f_tc_lu_imsi_auth_tmsi_encr_3_1), 360);
+	vc_conn.done;
+}
+testcase TC_lu_imsi_auth_tmsi_encr_3_1_no_cm() runs on MTC_CT {
+	var BSC_ConnHdlrPars pars;
+	var BSC_ConnHdlr vc_conn;
+	f_init();
+	f_vty_config(MSCVTY, "network", "authentication required");
+	f_vty_config(MSCVTY, "network", "encryption a5 3");
+
+	pars := f_init_pars(361);
+	pars.send_early_cm := false;
+	vc_conn := f_start_handler_with_pars(refers(f_tc_lu_imsi_auth_tmsi_encr_3_1), pars);
 	vc_conn.done;
 }
 
@@ -1624,6 +1640,7 @@
 	execute( TC_lu_imsi_auth_tmsi_encr_1_13() );
 	execute( TC_lu_imsi_auth_tmsi_encr_3_13() );
 	execute( TC_lu_imsi_auth_tmsi_encr_3_1() );
+	execute( TC_lu_imsi_auth_tmsi_encr_3_1_no_cm() );
 	execute( TC_lu_imsi_auth_tmsi_encr_13_2() );
 	execute( TC_lu_imsi_auth_tmsi_encr_013_2() );