--- a/lib/DNS/Vi.pm	Wed Jun 04 14:47:45 2014 +0200
+++ b/lib/DNS/Vi.pm	Wed Jun 04 14:50:38 2014 +0200
@@ -161,6 +161,7 @@
           $len2 => $r{rrtype},
           $r{data};
     };
+    push @out, '; do NOT EDIT the SOA records SERIAL number!';
     push @out, $print->($_) foreach @zone;
     return join "\n", @out, '';
 }