Try: 
    $Torrentz_Interface->submit_form(
        form_number => 1,
        fields      => {
            user       => $username,
            pass       => $password,
        },
        button => "go"
    );

[download]
If this does not help -- it may be JavaScript cookies (or cookies which you get downloading some small file: css or image).

In reply to Re: WWW Mechanize submit_form issue by Gangabass
in thread WWW Mechanize submit_form issue by oldnut

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