Christians agree that Easter is computed using a lunar calendar, however, various sects use different methods for computing lunar leap months. Passover is also on the lunar calendar.
Easter (or Pascha/some derivative as it's called in most non-English countries - which comes from Passover) is basically Passover + a bunch of days (remember the story of the Crucifixion then Resurrection).
My mistake. For some reason I was thinking there was still some component of the Julian calendar used with the calculation even though it is lunar based.
