function createRequestObject() {
 var ro;
  if(navigator.appName == "Microsoft Internet Explorer"){
     ro = new ActiveXObject("Microsoft.XMLHTTP"); } else {
     ro = new XMLHttpRequest();}
     return ro;  }

var http = createRequestObject();
 function sendRequest(email){
  http.open('get', 'checkmail.php?email=' + encodeURIComponent(email));
  http.onreadystatechange = handleResponse;
  http.send(null); }

function handleResponse(){
 if(http.readyState == 4){
  if(http.status == 200 || http.status == 304){
     document.getElementById('fname').value = '';
     document.getElementById('lname').value = '';
        var valuez = eval( http.responseText);
     document.getElementById('fname').value = valuez[0];
     document.getElementById('lname').value = valuez[1];
     
  }
 }
}