ajax not loading on first click

Here's my problem.

I have some link that trigger ajax function to load the content in a div. It working fine in Chrome and FireFox. However there is an issue in IE.It react funny. If i click on a link for the first time since the page is loaded it wont work as expected. It will load on the second click or if i mouse over the area that should be updated. And only IE react like that.

My Javascript function to query data 

function req_frame(box,user,action,product) {
var xhr = getXMLHttpRequest();
    xhr.onreadystatechange = function() {

         if (xhr.readyState == 4 && (xhr.status == 200 || xhr.status == 0)) {
    parent.frames[user].document.getElementById(box).innerHTML=xhr.responseText;
        }

    };

    var sVar1 = product;
    var sVar3 = encodeURIComponent(user);
    var sVar2 = encodeURIComponent(action);


    xhr.open("GET", "ajax_http.php?variable1=" + sVar3 + "&am开发者_运维技巧p;variable2=" + sVar2 + "&variable3=" + sVar1, true);
    xhr.send(null);

}

I know this code is working cuse well it is! even tho the var are a lil mixed up

And i call this function using event triggering with Jquery like that

$("#ajphoto").live('click', function(){ req_frame("framebox","contpic","ajphoto","product"); })     

Anyone wana help? Thanks

---

try this:

function req_frame(box,user,action,product) {
  var result = $(parent.frames[user].document.getElementById(box));
  result.load("ajax_http.php", 
    {variable1:user, variable2:action, variable3:product});
}