//------------------------------------------------------------------------------
function makeRequest(url, funcOnOk, funcOnError, _post)
{
    var http_request = false;

    if (window.XMLHttpRequest) { // Mozilla, Safari,...
        http_request = new XMLHttpRequest();
        if (http_request.overrideMimeType) {
            http_request.overrideMimeType('text/xml');
            // See note below about this line
        }
    } else if (window.ActiveXObject) { // IE
        try {
            http_request = new ActiveXObject("Msxml2.XMLHTTP");
        } catch (e) {
            try {
                http_request = new ActiveXObject("Microsoft.XMLHTTP");
            } catch (e) {}
        }
    }

    if (!http_request) {
        alert('Giving up :( Cannot create an XMLHTTP instance');
        return false;
    }
    http_request.onreadystatechange = function() { alertContents(http_request, funcOnOk, funcOnError); };
	
    if (typeof _post == "undefined") {
        http_request.open('GET', url, true);
        http_request.send(null);	
    } else {
        http_request.open('POST', url, true);
        http_request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
        http_request.send(_post);
	
    }
}

//------------------------------------------------------------------------------
function alertContents(http_request, funcOnOk, funcOnError)
{
    if (http_request.readyState == 4) {
        if (http_request.status == 200) {
            funcOnOk(http_request);
        } else {
            funcOnError(http_request);
        }
    }
}