diff --git a/hlr/HLR_Tests.ttcn b/hlr/HLR_Tests.ttcn
index b6bd1ad..e58515b 100644
--- a/hlr/HLR_Tests.ttcn
+++ b/hlr/HLR_Tests.ttcn
@@ -302,6 +302,14 @@
 	}
 }
 
+function f_vty_transceive_nomatch(TELNETasp_PT pt, charstring cmd, template charstring exp_ret) {
+	var charstring ret := f_vty_transceive_ret(pt, cmd);
+	if (match(ret, exp_ret)) {
+		setverdict(fail, "Matching VTY response: ", ret, ", should *not* have matched: ", exp_ret);
+		mtc.stop;
+	}
+}
+
 private template (value) charstring t_subscr_prefix(hexstring imsi) :=
 	"subscriber imsi " & hex2str(imsi) & " ";
 
@@ -351,6 +359,11 @@
 	f_vty_transceive_match(VTY, prefix & "show", exp);
 }
 
+/* perform 'show' on subscriber; result must not match with pattern 'exp' */
+function f_vty_subscr_show_nomatch(TELNETasp_PT VTY, HlrSubscriber sub, template charstring exp) {
+	var charstring prefix := valueof(t_subscr_prefix(sub.imsi));
+	f_vty_transceive_nomatch(VTY, prefix & "show", exp);
+}
 
 /***********************************************************************
  * Helper functions for ConnHdlr