/* XMLHttprequest functions */

function load(url, target_div_id, args, callback){

        // cheating here to add session id to all ajax calls
        url = url + sessid;

        var req = 0;

        if(window.XMLHttpRequest) {
                req = new XMLHttpRequest();
        } else {
                req = new ActiveXObject("Microsoft.XMLHTTP");
        }

        req.onreadystatechange = function() { process_request(req, target_div_id, callback); };
        req.open("POST", url, true);
        req.setRequestHeader("Content-Type","application/x-www-form-urlencoded; charset=UTF-8");
        req.send(args);


}

function process_request(req, target_div_id, callback){
    // only if req shows "complete"

    if (req.readyState == 4) {
        if (req.status == 200) {
            if(target_div_id){
                //alert(req.responseText);
                var target_div = document.getElementById(target_div_id);
                target_div.innerHTML = req.responseText;
                if(callback){
                                        callback();
                }
            }
        }
    }
}