# File cron/lib/symbiosis/crontab.rb, line 293
    def initialize(min, hour, mday, mon, wday, command)
      @min  = parse_field(min,  0, 59)
      @hour = parse_field(hour, 0, 23)
      @mday = parse_field(mday, 1, 31)
      @mon  = parse_field(mon,  1, 12)
      @wday = parse_field(wday, 0, 7)

      # normalize weekdays
      @wday = @wday.collect{|w| w == 7 ? 0 : w }.sort.uniq

      self.command = command
    end