Repeat the first Mon, Tues, Wed Help!

Greetings

How do I get iCal to repeat an event period every month.. ie.. I want the first Monday, Tuesday and Wednesday to be an event.

My local health shop has a discount on the first Monday, Tuesday and Wednesday of every month! Since I've started using the iCal Events widget, I found iCal to be a great deal more useful.. except I cannot figure out how to do what I've asked!

Any help?