public static function _recaptcha_aes_encrypt($val, $ky)
 {
     if (!function_exists("mcrypt_encrypt")) {
         die("To use reCAPTCHA Mailhide, you need to have the mcrypt php module installed.");
     }
     $mode = MCRYPT_MODE_CBC;
     $enc = MCRYPT_RIJNDAEL_128;
     $val = RecaptchaForDekoBoko::_recaptcha_aes_pad($val);
     return mcrypt_encrypt($enc, $ky, $val, $mode, "");
 }