function makeHttpRequest(url, callback_function, return_xml)
{
   var ajaxRequest;

   if (window.XMLHttpRequest) 
   		{ // Mozilla, Safari,...
       		ajaxRequest = new XMLHttpRequest();
       		if (ajaxRequest.overrideMimeType) 
				{
           			ajaxRequest.overrideMimeType('text/xml');
       			}
   		} 
	else if (window.ActiveXObject) 
		{ // IE
       		try 
				{
           			ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
       			} 
			catch (e) 
				{
           			try 
						{
               			ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
           				} 
					catch (e) {}
       			}
   		}
   if (!ajaxRequest) 
   		{
       		alert('Unfortunatelly you browser doesn\'t support this feature.');
       		return false;
   		}
   ajaxRequest.onreadystatechange = function() {
       if (ajaxRequest.readyState == 4) {
           if (ajaxRequest.status == 200) {
               if (return_xml) {
                   eval(callback_function + '(ajaxRequest.responseXML)');
               } else {
                   eval(callback_function + '(ajaxRequest.responseText)');
               }
           } else {
               alert('There was a problem with the request.(Code: ' + ajaxRequest.status + ')');
           }
       }
   }
   ajaxRequest.open('GET', url, true);
   ajaxRequest.send(null);
}

function loadBanner(xml)
{
    var html_content = xml.getElementsByTagName('content').item(0).firstChild.nodeValue;
    var reload_after = xml.getElementsByTagName('reload').item(0).firstChild.nodeValue;
    document.getElementById('ajax-banner').innerHTML = html_content;

    try {
        clearTimeout(to);
    } catch (e) {}

    to = setTimeout("nextAd()", parseInt(reload_after));


}

function nextAd()
{
    var now = new Date();
    var url = '../../rotbns/ajax-banner.php?ts=' + now.getTime();
    makeHttpRequest(url, 'loadBanner', true);
}

window.onload = nextAd;