function isDate(s)
{
    if(!/\d\d\/\d\d\/\d\d\d\d/.test(s))
        return false;
    var a = s.split('/');
    var d = new Date(a[2], parseFloat(a[1]) - 1, a[0]);
    if(d.getDay()==2&&parseFloat(a[1])==1&&parseFloat(a[0])<8&&d.getHours()==23) // KB2998527
        d = new Date(a[2], parseFloat(a[1]) - 1, a[0], 1);
    if(a[2] < 1989)
        return false;
    return (!isNaN(d)) && (parseFloat(a[0]) == d.getDate()) && a[0].length == 2 && (parseFloat(a[1]) == (d.getMonth() + 1)) && a[1].length == 2 &&  (a[2] == d.getFullYear());
}