//asynchroniczne zadanie sprawdzenia czy login jest w uzyciu
var req = null;
function syncRequest(url, postData) {
    var noCache = 'timeId=' + new Date().getTime();
    if (url.indexOf('?') >= 0) {
		url = url + '&' + noCache;
    } else {
		url = url + '?' + noCache;
    }
	
	req = getXMLHttpObj();
    req.open("POST", url, false);
    req.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    
    var data = '';
	for (key in postData) {
		data += key + '=' + postData[key] + '&';
	}
    req.send(data);
	
	return req.responseText;
}

function getXMLHttpObj(){
	if(typeof(XMLHttpRequest)!='undefined')
		return new XMLHttpRequest();
	var axO=['Msxml2.XMLHTTP.6.0', 'Msxml2.XMLHTTP.4.0',
		'Msxml2.XMLHTTP.3.0', 'Msxml2.XMLHTTP', 'Microsoft.XMLHTTP'], i;
	for(i=0;i<axO.length;i++)
		try{
			return new ActiveXObject(axO[i]);
		}catch(e){}
	return null;
}