vBulletin login with WWW::Mechanize

This is just part of a script that I wrote to...do something. The pertinent part here is using WWW::Mechanize to login to a vBulletin web forum. I figure Googlebot will guide someone trying to figure out how to use WWW::Mechanize this way.

use WWW::Mechanize;
my $username = "foo";
my $password = "bar";
my $forum = "http://www.foo.com/forum/";

my $mech = WWW::Mechanize->new  (
                                    autocheck   =>  1,
                                    agent       =>  'Perl WWW::Mechanize',
                                );

$mech->get( $forum );
$mech->submit_form(
                        form_number =>  1,
                        fields      =>  {
                                            vb_login_username => $username,
                                            vb_login_password => $password
                                        }
                    );
$mech->follow_link(
    text => "Click here if your browser does not automatically redirect you."
    );