what am i doing wrong, it does not echo "hello"......ths page is unt.php
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
<script type="text/javascript">
var ht=false;
if(navigator.appName=="Microsoft Internet Explorer")
{
ht=new ActivxObject("Microsoft.XMLHTTP");
}
else
{
ht=new XMLHttpRequest();
}
function chkLogin()
{
if(ht!=null)
{
document.getElementById('error').innerHTML="Loading plz wait....";
var idd=document.getElementById('uid').value;
var psw=document.getElementById('pass').value;
ht.open("GET","unt.php?id="+idd,true);
ht.onreadystatechange=function(){
if(ht.readyState==4){
alert('yeah');
}
}
http.send(null);
}
else
{
alert('Nahi support');
}
}
</script>
</head>
<body>
<?php
if(isset($_GET['id'])){echo("hello!");}
?>
<form action="javascript:chkLogin()" method="post" ">
<input name="id" type="text" id="uid" />
<br />
<input name="pass" type="password" id="pass" />
<br />
<input name="sub" type="submit" id="submit" />
</form>
<div id="result"></div>
<div id="error"></div>
<div id="load"></div>
</body>
</html>