Thanks for the responses … as I said I wrote my own handler as an exercise in learning. Probably once having done it to understand the process, I should have have switched back to a standard library. I would never have recognised (without your help…

Like BK said you have global variables all over the place and this breaks the code. You have to think about what happens when your methods are called concurrently. For example “console” will be overwritten by the latest call, since it’s a global var…

First thing, even though you don’t define the global var, since you probably didn’t add var in front of xmlReq=startXMLHTTPRequest();
it is still considered a global variable. This means that when you test readyState, you don’t necessarily test th…

The sendRequest object. Since reading about the global var I have tried removing the “var xmlReq;” line from code and there is no difference in behaviour. The final call still gets executed while the rest stay on “sending”. I can certainly see t…

If this is the cause I shall return to my cave happy and stop mashing my face into the keyboard.

var xmlReq;

function sendRequest(url, params, HttpMethod){

if(!HttpMethod) {
HttpMethod=”POST”;
}

xmlReq=startXMLHTTPRequest();

if(xmlReq) {

xmlReq.onreadystatechange=onReadyState;
xmlReq.open(HttpMethod,url,true);
xmlReq.send(params);
}
}

function startXMLHTTPRequest(){

var req=null;

try {
req=new ActiveXObject(“Microsoft.XMLHTTP”);
}
catch(e)
{
req=new XMLHttpRequest()
}

return req;

}

function onReadyState()
{
var readyXML=xmlReq.readyState;
var data=null;

if(readyXML == 4){
if(xmlReq.status == 200) {
console.innerHTML=”;
data=xmlReq.responseText;
}
else {
data=xmlReq.status;
}
}
else{
console.innerHTML=”;

if(readyXML == 3){
data=”Serving …”;
}
if(readyXML == 2){
data=”Loading …”;
}
if(readyXML == 1){
data=”Sending …”;
}
}

dataInnerHTML(data);
}

function dataInnerHTML(data){

if(data!=null){
var newline=document.createElement(“div”);
console.appendChild(newline);
newline.innerHTML+=”"+data+”";
}

}

Are you sure you don’t have a race condition sneaking in there somewhere in sendRequest()? I’d like to see the implementation of that method to really make sure. No global variables or something obvious like that?
…