WPMU Calendar

Hi Everyone -

I did search the forums (and google) to see if there are any WPMU Calendars out there, but all of the discussions were a year old or older...

Please let me know what is the best way of reaching the following goal:

WPMU is set up as a "department home" site. We need a "department-wide" events calendar.

a) Do I need a Calendar that works with WPMU? Which one?

or

b) Do I need to set up a single "blog" called "events", and then install the best "regular" events calendar out there (for lectures, meetings - hopefully filterable by event category & with user submitted events - which calendar do you like?) In this case I would need to make sure that everyone who wants to submit events would get an account on this "events" blog...

What would you recommend? (Do I even have a choice of using a "regular" WP calendar on a single WPMU blog?)

Victor