running cron with drupal.sh

I'd like to be able to run cron using drupal.sh located in the scripts folder. I've read that you can run cron.php more securely, blocking cron.php from the web, using this method. I can't seem to get it to work. I'm on suse linux 10.1. However, I have seen little to nothing discussing this method. Since this new in Drupal 6, I'd like to use it. Any explanation or link to an explanation is appreciated.

cheers,

wim