Open iCal to a specific CalEvent from Objective-C

10.6, Cocoa only (no Applescript). I have a CalEvent and I want to open it in iCal. How?

I can open iCal URLs with NSWorkspace using URLs of the notation: "ical://" but I can't find documentation on the syntax of the URL that would allow me to specify a specific CalEVent's uid. I tried simply appending the UID tot he end of the "ical://" string, but that only opened iCal, it didn't display a view containing the event with the uid specified.

I thought there might be a method for opening iCal from a CalEvent in the Calendar Framework, but no such method has been found.

I then examined how Mail's "To Do" feature stores a URL back to a message, it uses this syntax:

mailitem:4019BCA5-4226-410B-969A-AEBAC75C3AE8?type=todo&action=showparent

So I tried variations of that, substituing in my event's uid for that UUID and "ical" or "calendaritem" etc, but no go.

Ideas?

thanks