I want to mass edit all events in an ical file

I have an ical file that holds 1200 events, four events each day, 25 days each month. It's a yearly schedule. Trouble is, none of the events are set to repeat yearly, so the events aren't rolling over into 2009. Manually editing 1200 events is less that appealing.

Is there a way I can edit all the events on the calendar to repeat yearly?

export, edit, import

I just had the same problem. I exported the calendar to my desktop, opened the .ics file in TextEdit, and used the find and replace function to fix it -

I found the text "END:VEVENT" and
replaced it with "RRULE:FREQ=YEARLY;INTERVAL=1 {enter, as in, I hit enter, to start a new line} END:VEVENT"

- then imported the calendar back into ical and deleted the old calendar. It was a birthdays calendar, so the replacement text was relatively simple. Good luck with all that sh*t you've got