You can change only function BfishCompose :
public function BfishCompose(array $parameters)
{
// compose Blowfish hex string
$blowfishString = '';
foreach($parameters as $key) {
if(array_key_exists($key, $this->parameters) && !empty($this->parameters[$key])) {
$value = $this->parameters[$key];
$blowfishString .= $key.'='.$value.'&';
}
}
//add this
$blowfishString.='MsgVer=2.0&';
$blowfishString = rtrim($blowfishString,'&');
$this->parameters['Debug'] = $blowfishString;
$this->parameters['Len'] = strlen($blowfishString);
$this->parameters[self::DATA_FIELD] = bin2hex($this->encrypt($blowfishString,$this->cryptKey));
return $this->parameters[self::DATA_FIELD];
}