function switchVisible(elId) {
    var elt = findElementByID(elId);
    if (elt.style.visibility == "hidden") elt.style.visibility = "visible";
    else  elt.style.visibility = "hidden";
}
function setVisible(elId) {
    var elt = findElementByID(elId);
    elt.style.visibility = "visible";
    clearTimeout(c["at_timeout"]);
}
function setHiddenWithTimeOut(elId, timeout) {
    var elt = findElementByID(elId);
    elt["at_timeout"] = setTimeout("findElementByID('" + elId + "').style.visibility = 'hidden';", timeout);
}
function setHidden(elId) {
    setHiddenWithTimeOut(elId, 0); 
}