function isValidDate(myDate) {
  if(myDate.indexOf('/') != -1) {
    splitDate = myDate.split('/');
  } else {
    return false;
  }
  
  if(splitDate.length != 3 || isNaN(splitDate[0]) || isNaN(splitDate[1]) || isNaN(splitDate[2]) ||
    (splitDate[0].length != 1 && splitDate[0].length != 2) ||
    (splitDate[1].length != 1 && splitDate[1].length != 2) ||
    splitDate[2].length != 4) {
    
    return false;
  }
  
  var year = y2k(splitDate[2]);
  var test = new Date(year,splitDate[0] - 1,splitDate[1]);
  
  if(year == y2k(test.getYear()) && (splitDate[0] - 1 == test.getMonth()) && (splitDate[1] == test.getDate())) {
    return true;
  } else {
    return false;
  }
}

function y2k(number) {return (number < 1000) ? number + 1900 : number; }

function getXMLHTTPObject() {
    var xmlHTTP = null;
    try {
        // Firefox, Opera 8.0+, Safari
        xmlHTTP=new XMLHttpRequest();
    } catch (e) {
        // Internet Explorer
        try {
            xmlHTTP=new ActiveXObject("Msxml2.XMLHTTP");
        } catch (e) {
            try {
                xmlHTTP=new ActiveXObject("Microsoft.XMLHTTP");
            } catch (e) {
                alert("Your browser does not support AJAX!");
                return false;
            }
        }
    }
    
    return xmlHTTP;
}