public static function loadClass($className){


		// handle only package classes
		if(strpos($className, 'Less_') !== 0){
			return;
		}

		$className = substr($className,5);
		$fileName = self::$libDir . DIRECTORY_SEPARATOR . str_replace('_', DIRECTORY_SEPARATOR, $className) . '.php';

		if(file_exists($fileName)){
			require $fileName;
			return true;
		}else{
			throw new Exception('file not loadable '.$fileName);
		}
	}