diff --git a/t/config.t b/t/config.t
index 8b6b11e..975e8d5 100644
--- a/t/config.t
+++ b/t/config.t
@@ -25,7 +25,9 @@ is($smtpd->config('me'), 'some.host.example.org', 'config("me")');
 # test for ignoring leading/trailing whitespace (relayclients has a
 # line with both)
 my $relayclients = join ",", sort $smtpd->config('relayclients');
-is($relayclients, '127.0.0.1,192.0.', 'config("relayclients") are trimmed');
+is($relayclients,
+	'127.0.0.1,192.0.,2001:0DB8:0000:0000:0000:0000:0000:0001,2001:DB8,2001:DB8::1',
+	'config("relayclients") are trimmed');
 
 foreach my $f ( @mes ) {
     unlink $f if -f $f;