Create Internet calendar in Outlook 2007 from a Drupal ical feed?

Hi

I tried searching for information about this subject but it just got me more confused (expecially about which modules are involved in all this)

Outlook 2007 now offer the option to have internet calendar from .ics feeds.

In my installation of Drupal, we offer .ics files on calendar pages (The module I use is Event 5.x-1.0)

When a user clicks on it, he can download the ics file and import the events in his calendar, but its static : new changes arent shown.

I tried creating an internet calendar using the adress my ics file comes from ( ..../event/ical/calendar.ics or ..../event/ical/all/all/calendar.ics) but Outlook can't get the information from there (there's never any update)

Is this possible? Is there a module I need to install or something i need to configure to have a ics feed people can subscribe to?

Thanks