var url_skype_status = '/data/skype_button.inc.php';

function makeRequest(url) {
    var httpRequest;

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

    if (!httpRequest) {
        return false;
    }
    httpRequest.onreadystatechange = function() { alertContents(httpRequest); };
    httpRequest.open('GET', url, true);
    httpRequest.send(null);

}

function alertContents(httpRequest) {

    if (httpRequest.readyState == 4) {
        if (httpRequest.status == 200) {
            var html_skype_status = document.getElementById('skype_button');
            if (html_skype_status.innerHTML != httpRequest.responseText) {
              document.getElementById('skype_button').innerHTML = httpRequest.responseText;
            }
            
            setTimeout('makeRequest(url_skype_status);', 10000); 
        }
    }

}