var frame_height = 0;
    function scrollbanners() {
        frame_height = 0;
        if (document.getElementById) {
            bannerDiv = document.getElementById("banners");
            if(bannerDiv) {
                if (parseInt(bannerDiv.style.top) > document.getElementById('bannerList').offsetHeight - bannerDiv.offsetHeight) { 
                    // reset when second edition of first banner reached the top
                    if (parseInt(bannerDiv.style.top) < frame_height) {
                        bannerDiv.style.top = "0px";
                    }
                    else {
                        bannerDiv.style.top = parseInt(bannerDiv.style.top) - 1 + "px";
                    }
                    timer = setTimeout("scrollbanners()",25);
                }
            }
        }
    }