Fatal error under PHP5.1

You get a fatal error for reference misuse under php5.1
Fix by changing line 35 of banners.module // $Id: banner.module,v 1.52 2005/07/15 13:03:00 jeremy Exp $
from :
if (!file_check_directory(file_create_path(variable_get('banner_image_path', 'banners')), FILE_CREATE_DIRECTORY)) {
to :
if (!file_check_directory($dir =& file_create_path(variable_get('banner_image_path', 'banners')), FILE_CREATE_DIRECTORY)) {