iCal 5.0.3 Repeat pop-up menu not appearing

I created a new calendar and then copied events from the previous year into it. Now I'm trying to set events to repeat yearly, but when I pull up the event, I'm not getting the pop-up menu that allows me to reset the time or repetition. This problem only seems to happen in the events I copied from the previous calendar. Is there anything I can do, short of re-typing each event?