It can be tricky sending email from a batch script (e.g. for cron use), here's how to do it. Start with your usual batch setup:

define('SF_ROOT_DIR',    realpath(dirname(__FILE__).'/..'));
define('SF_APP',         'app_name');
define('SF_ENVIRONMENT', 'environment');
define('SF_DEBUG',       true);
 
require_once(SF_ROOT_DIR.DIRECTORY_SEPARATOR.'apps'.DIRECTORY_SEPARATOR.SF_APP.DIRECTORY_SEPARATOR.'config'.DIRECTORY_SEPARATOR.'config.php');
sfContext::getInstance();

You can set attributes directly from the batch script if you wish:

sfContext::getInstance()->getRequest()->setAttribute('key', $value);

Then forward on to another module/action to handle processing and forwarding to mail as usual:

sfContext::getInstance()->getController()->forward('action', 'module');