function validate() {
	var fail = 0;
	mFields = ["fullname", "email", "username", "password1", "password2"];
	mFields.each(function(field){
		if (!fail) {
			elem = document.getElementById(field);
			if (elem) {
				if (elem.value=='') {
					fail = 1;
				}
			} else {
				var i = 1;
				fail = 1;
				elem = document.getElementById(field+'_'+i);
				while (elem) {
					if (elem.checked) {
						fail = 0;
						break;
					}
					i++;
					elem = document.getElementById(field+'_'+i);
				}
			}
		}	
	});
	if (fail) {
		alert("Please fill in all mandatory fields.");
		return false;
	}
	return true;
}