// XMLhttpRequest stuff
var aXmlHttp = new Array();
var aXmlResponse = new Array();

function xmlResult() {
    for (var i = 0; i < aXmlHttp.length; i++) {
        if (aXmlHttp[i] && aXmlHttp[i][0] && aXmlHttp[i][0].readyState == 4) {
            // must null out record before calling function in case
            // function invokes another xmlHttpRequest.
            var f = aXmlHttp[i][1];
            var s = aXmlHttp[i][0].responseText;
            aXmlHttp[i][0] = null;
            aXmlHttp[i][1] = null;
            aXmlHttp[i] = null;
            f(s);
        }
    }
}

// u -> url
// f -> callback
function call(u, f) {
    var idx = aXmlHttp.length;
    for(var i = 0; i < idx; i++)
        if (aXmlHttp[i] == null) {
            idx = i;
            break;
        }
    aXmlHttp[idx] = new Array(2);
    aXmlHttp[idx][0] = getXMLHTTP();
    aXmlHttp[idx][1] = f;
    if(aXmlHttp[idx]) {
        aXmlHttp[idx][0].open("GET", u, true);
        aXmlHttp[idx][0].onreadystatechange = xmlResult;
        aXmlHttp[idx][0].send(null);
    }
}

function getXMLHTTP() {
    var A = null;
    try {
        A = new ActiveXObject("Msxml2.XMLHTTP")
    }
    catch(e) {
        try {
            A = new ActiveXObject("Microsoft.XMLHTTP")
        }
        catch(oc) {
            A = null
        }
    }
    if(!A && typeof XMLHttpRequest != "undefined") {
        A = new XMLHttpRequest()
    }
    return A
}

function drawNull(s) {
    eval(s);
    return false;
}