or download this
# Code derived from Email::MessageID 1.406 by Ricardo Signes
# http://cpansearch.perl.org/src/RJBS/Email-MessageID-1.406/lib/Email/
+MessageID.pm
...
my $user = join '.', $t . $u, $noise, $$;
return '<' . $user . '@' . hostname_long . '>';
}