If you use the great jquery countdown plugin with a datetime object from you database you may encounter some invalid date object errors in Firefox and/or IE. This code takes care of that issue by using a regex. Make sure your countdown_date string datetime is like the one used in this code.

countdown_timer.js

// jquery countdown: http://keith-wood.name/countdown.html
var countdown_date = "07-05-1990 02:00";
var dateRegex = countdown_date.match(/(\d{2})-(\d{2})-(\d{4}) (.*)/);
var newDate = dateRegex[3] + "/" + dateRegex[2] + "/" + dateRegex[1] + " " + dateRegex[4];
var date = new Date(newDate);
$(".countdown-timer").countdown({until: date, format: "YODH", padZeroes: true});