var preloadFlag = false;

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

function changeImages(name, image) {
    if (document.images && (preloadFlag == true)) {
        document[name].src = image;
    }
}

function preloadImages() {
    if (document.images) {
        menu_03_over = newImage("images/menu_03_over.gif");
        menu_05_over = newImage("images/menu_05_over.gif");
        menu_07_over = newImage("images/menu_07_over.gif");
        menu_09_over = newImage("images/menu_09_over.gif");
        menu_11_over = newImage("images/menu_11_over.gif");

        preloadFlag = true;
    }
}