function swapImage(obj,str) {
    var newSrc = obj.src;
    var i = newSrc.indexOf("_");
    if (i > -1) {
        newSrc = newSrc.substring(0,i) + "_" + str + ".jpg";
        obj.src = newSrc;
    }
}
function setFooter() {
    var f = document.getElementById("footer");
    //alert("top=" + f.offsetTop + "-height=" + f.offsetHeight + "-bodyheight=" + document.body.clientHeight);
    if ((f.offsetTop + f.offsetHeight) < document.body.scrollHeight) {
        var l = document.body.scrollHeight - f.offsetHeight;
        f.style.top = l + "px";
    }
}