var http_request = false;
   var obiekt
   function makePOSTRequest(url, parameters) {
      http_request = false;
      if (window.XMLHttpRequest) {
         http_request = new XMLHttpRequest();
         if (http_request.overrideMimeType) {
            http_request.overrideMimeType('text/html');
         }
      } else if (window.ActiveXObject) {
         try {
            http_request = new ActiveXObject("Msxml2.XMLHTTP");
         } catch (e) {
            try {
               http_request = new ActiveXObject("Microsoft.XMLHTTP");
            } catch (e) {}
         }
      }
      if (!http_request) {
         alert('Nie można stworzyć instancji XMLHTTP.');
         return false;
      }

      http_request.onreadystatechange = alertContents;
      http_request.open('POST', url, true);
      http_request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
      http_request.setRequestHeader("Content-length", parameters.length);
      http_request.send(parameters);
   }

   function alertContents() {
      if (http_request.readyState == 4) {
         if (http_request.status == 200) {
            var result = http_request.responseText;
            if (result == '1') {obiekt.style.color = '#FF0000';}
            if (result == '0') {obiekt.style.color = '#000000';}
         } else {
            alert('Wystąpił problem z realizacją żądania.');
         }
      }
   }


   function buttonClicked(obj) {
      obiekt=obj;
      var poststr = 'x=' + encodeURI( obj.value );
      makePOSTRequest('aa.php', poststr);
   }