function Joom_Chmod($dir, $mode = 0644) { 
  static $ftpOptions;
 
  if(!isset($ftpOptions)) {
    // Initialize variables
    jimport('joomla.client.helper');
    $ftpOptions = JClientHelper::getCredentials('ftp');
  }
 
  if ($ftpOptions['enabled'] == 1) {   
    //check if chmod is necessary, otherwise return true  
    $fileperms= substr(decoct( fileperms($dir)),3);
    if ($fileperms >= decoct($mode)){
      return true;
    } 
    // Connect the FTP client
    jimport('joomla.client.ftp');
    $ftp = &JFTP::getInstance(
      $ftpOptions['host'], $ftpOptions['port'], null,
      $ftpOptions['user'], $ftpOptions['pass']
    );
    // Translate path to FTP path
    $dir = JPath::clean(str_replace(JPATH_ROOT, $ftpOptions['root'], $dir), '/');
    $ftp->chmod($dir, $mode);
  } 
  return true;
}