var
	monthLength = new Array(31,28,31,30,31,30,31,31,30,31,30,31),
	minyear = 1970,
	maxyear = 2069,
	separateur = "/";

function isValidDate(date)
{
var
	day = date.substring(0, 2),
	month = date.substring(3, 5),
	year = date.substring(6);
	
	if (date.substring(2,3) != separateur || date.substring(5,6) != separateur)
		return false;

	if (!day || isNaN(day) || !month || isNaN(month) || !year || isNaN(year))
		return false;

	if (month < 1 || month > 12)
		return false;

	if (year <= minyear || year >= maxyear)
		return false;

	if (year/4 == parseInt(year/4))
		monthLength[1] = 29;

	if (day > monthLength[month-1])
		return false;

	monthLength[1] = 28;

	return true;
}