function swapImage(imgObj, strImg) {
    imgObj.old = imgObj.src;
    imgObj.src = strImg;
}

function restoreImage(imgObj) {
    imgObj.src = imgObj.old;
}

var __g_menuTimer = null;
function showMenu(menuId) {
    if (__g_menuTimer) {
        clearTimeout(__g_menuTimer);
        __g_menuTimer = null;
    }
    dojo.style(menuId, "visibility", "visible");
}

function hideMenu(menuId) {
    if (__g_menuTimer)
        return;

    __g_menuTimer = window.setTimeout(function() {
        dojo.style(menuId, "visibility", "hidden");
    }, 300);
}