How to show Ajax requests in URL?

HTML

<a href="/bye.php?user=abc&page=messages" 
   onclick="return goToWithAjax(this);">bye</a> 

Javascript

function goToWithAjax(hash) {
  hash = hash.href ? hash.getAttribute("href", 2) : hash;
  ajax( hash, function( response ) {
    document.getElementById("content").innerHTML = response;
  });
  hash = ("#!/" + hash).replace("//","/");
  window.location.hash = hash;
  return false;
}

//////////////////////////////////////////////////////////////////////////////

function getXmlHttpObject() {
    var xmlHttp;
    try {
        xmlHttp = new XMLHttpRequest();
    } catch (e) {
        try {
            xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
        } catch (e) {
            xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
        }
    }
    return xmlHttp;
}

function ajax(url, onSuccess, onError) {
    var xmlHttp = getXmlHttpObject();
    xmlHttp.onreadystatechange = function () {
        if (this.readyState == 4) {
            // onError
            if (this.status != 200) {
                if (typeof onError == 'function') {
                    onError(this.responseText);
                }
            }
            // onSuccess
            else if (typeof onSuccess == 'function') {
                onSuccess(this.responseText);
            }
        }
    };
    xmlHttp.open("GET", url, true);
    xmlHttp.send(null);
    return xmlHttp;
}​