function newImage(arg) {
        if (document.images) {
          rslt = new Image();
          rslt.src = arg;
          return rslt;
        }
      }

      function changeImages() {
        if (document.images && (preloadFlag == true)) {
          for (var i=0; i<changeImages.arguments.length; i+=2) {
            document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
          }
        }
      }

      var preloadFlag = false;
      function preloadImages() {
        if (document.images) {
          suche_over          = newImage("./img/suche_over.gif");
          sitemap_over        = newImage("./img/sitemap_over.gif");
          kontakt_over        = newImage("./img/kontakt_over.gif");
          formulare_over      = newImage("./img/formulare_over.gif");
          team_over           = newImage("./img/team_over.gif");
          all_buttons_over    = newImage("./img/button_over.gif");
          all_buttons_out     = newImage("./img/button_out.gif");
          all_buttons_click   = newImage("./img/button_click.gif");
          preloadFlag = true;
        }
      }