#!/usr/bin/perl
use WWW::Mechanize;
my $link = "https://localhost/query.cgi?GoAheadAndLogIn=1";
my $login = "x\@gx.com";
my $pass = "xx";
my $mech = WWW::Mechanize->new();
$mech->agent_alias( 'Windows IE 6' );
$mech->get( $link );
my %login = ( "Bugzilla_login"=> $login,
"Bugzilla_password"=> $pass);
$mech->set_fields(%login);
$mech->click( 'GoAheadAndLogIn' );

##</code><code>##

# ./bug.pl
No such field 'Bugzilla_password' at /usr/lib/perl5/site_perl/5.8.8/WWW/Mechanize.pm line 1265