contador regresivo

dt = new Date();
target = new Date(2006, 6, 30);
//El mes 6 es Julio (enero es el mes 0)
time = target.getTime()-dt.getTime();
brutDays = time/(3600000*24);
days = Math.floor(brutDays);
brutHours = (brutDays-days)*24;
hours = Math.floor(brutHours);
brutMinutes = (brutHours-hours)*60;
minutes = Math.floor(brutMinutes);
seconds = Math.floor((brutMinutes-minutes)*60);
trace(days);
trace(hours);
trace(minutes);
trace(seconds);