Code:
<script>
function displayMessage() {
var req = null;
if(window.XMLHttpRequest) {
    	try {
			req = new XMLHttpRequest();
        } catch(e) {
			req = false;
        }
    } else if(window.ActiveXObject) {
       	try {
        	req = new ActiveXObject("Msxml2.XMLHTTP");
      	} catch(e) {
        	try {
          		req = new ActiveXObject("Microsoft.XMLHTTP");
        	} catch(e) {
          		req = false;
        	}
		}
    }
		req.open("GET", "reload.php", true);
		req.onreadystatechange = function() {     
    if (req.readyState == 4) {
        if (req.status == 200) {
			         var chaine=req.responseText;
         var object=document.getElementById('chat');
		           if (chaine.length>4)
          {

         object.innerHTML= document.getElementById('chat').innerHTML+chaine;
         object.scrollTop=object.scrollHeight;
         
          }
        } else {
            alert("There was a problem retrieving the XML data:");
        }
    }
	setTimeout('displayMessage()',2500);
}
    req.send(null);
}


</script>
This code works perfectly on Fire fox. On my XP laptop - well - it hangs. Basically, IE stops responding. I check my Linux box running Fire fox, and the whole O/S is slow as hell. Basically, its a script for a chat box where both computers are talking - only when IE sends a message, or tries to receive a message - both computers hang.

I dunno what can be causing it since this is my first attempt at this script and I dunno even what language I am programming in.

Help much appreciated.

Oh, if you want to have a look at the script to test for yourself

http://www.fantasy-express.com/xmlchat/