diff --git a/bin/tests/system/tsiggss/authsock.pl b/bin/tests/system/tsiggss/authsock.pl
index d181b1a1d8..b3888fb061 100644
--- a/bin/tests/system/tsiggss/authsock.pl
+++ b/bin/tests/system/tsiggss/authsock.pl
@@ -59,6 +59,7 @@ if ($timeout != 0) {
 }
 
 while (my $client = $server->accept()) {
+	printf("accept()\n");
 	$client->recv(my $buf, 8, 0);
 	my ($version, $req_len) = unpack('N N', $buf);
 
diff --git a/bin/tests/system/tsiggss/clean.sh b/bin/tests/system/tsiggss/clean.sh
index 0ace209efb..ce885d5744 100644
--- a/bin/tests/system/tsiggss/clean.sh
+++ b/bin/tests/system/tsiggss/clean.sh
@@ -21,7 +21,7 @@ rm -f ns1/_default.tsigkeys
 rm -f */named.memstats
 rm -f */named.conf
 rm -f */named.run
-rm -f authsock.pid
+rm -f authsock.log authsock.pid
 rm -f ns1/core
 rm -f nsupdate.out*
 rm -f ns*/named.lock
diff --git a/bin/tests/system/tsiggss/tests.sh b/bin/tests/system/tsiggss/tests.sh
index a66570301e..34b8c890c7 100644
--- a/bin/tests/system/tsiggss/tests.sh
+++ b/bin/tests/system/tsiggss/tests.sh
@@ -116,7 +116,7 @@ status=$((status + ret))
 
 echo_i "testing external update policy (CNAME) with auth sock ($n)"
 ret=0
-$PERL ./authsock.pl --type=CNAME --path=ns1/auth.sock --pidfile=authsock.pid --timeout=120 >/dev/null 2>&1 &
+$PERL ./authsock.pl --type=CNAME --path=ns1/auth.sock --pidfile=authsock.pid --timeout=120 >authsock.log 2>&1 &
 sleep 1
 test_update $n testcname.example.nil. CNAME "86400 CNAME testdenied.example.nil" "testdenied" || ret=1
 n=$((n + 1))
@@ -130,17 +130,19 @@ n=$((n + 1))
 if [ "$ret" -ne 0 ]; then echo_i "failed"; fi
 status=$((status + ret))
 
-echo_i "testing external policy with SIG(0) key ($n)"
+echo_i "testing external policy with unsupported SIG(0) key ($n)"
 ret=0
-$NSUPDATE -k ns1/Kkey.example.nil.*.private <<END >/dev/null 2>&1 || ret=1
+$NSUPDATE -d -k ns1/Kkey.example.nil.*.private <<END >nsupdate.out${n} 2>&1 || true
+debug
 server 10.53.0.1 ${PORT}
 zone example.nil
 update add fred.example.nil 120 cname foo.bar.
 send
 END
 output=$($DIG $DIGOPTS +short cname fred.example.nil.)
-[ -n "$output" ] || ret=1
-[ $ret -eq 0 ] || echo_i "failed"
+# update must have failed - SIG(0) signer is not supported
+[ -n "$output" ] && ret=1
+grep -F "signer=key.example.nil" authsock.log >/dev/null && ret=1
 n=$((n + 1))
 if [ "$ret" -ne 0 ]; then echo_i "failed"; fi
 status=$((status + ret))