$mech->set_fields(
            'ctl00$ContentPlaceHolder1$ctl00$rcbusertype_Input' => "Subscriber",
            'ctl00$ContentPlaceHolder1$ctl00$txtUserName'    => $un,
            'ctl00$ContentPlaceHolder1$ctl00$txtPassword'    => $pw,
            ctl00_ContentPlaceHolder1_ctl00_rcbusertype_ClientState =>
            '{"logEntries":[],"value":"Subscriber","text":"Subscriber","enabled":true}'
);

my $response = $mech->click_button(
                            name => 'ctl00$ContentPlaceHolder1$ctl00$LoginButton',
                            x=>26,
                            y=>10
);