[Andreas]

Try this (untested)

bbcode_create

PHP Code:

$this->tag_list['no_option']['hideg']['callback'] = 'handle_external';
$this->tag_list['no_option']['hideg']['external_callback'] = 'handle_bbcode_hideg';
$this->tag_list['no_option']['hideg']['strip_empty'] = true;

if (!function_exists('handle_bbcode_hideg'))
{
    function handle_bbcode_hideg(&$parser, $text)
    {
        $parser->options['cachable'] = false;
        if (!$parser->registry->userinfo['userid'])
        {
            return '';
        }
        return $text;
    }
}