function getAge(o, now)
{
  var d = new Date(o.getTime());
  var age = -1;
  if (typeof(now) == 'undefined') now = new Date();
  while (now >= d)
  {
    age++;
    d.setFullYear(d.getFullYear() + 1);
  }
  return age;
}

var kirindob = new Date();
kirindob.setFullYear(1977,0,19);

var jamesdob = new Date();
jamesdob.setFullYear(1980,7,24);