var preloadFlag = false;
function preloadImages() {
    if (document.images) {
        pre_menu_01_over = newImage('images/menu_01-over.gif');
        pre_menu_02_over = newImage('images/menu_02-over.gif');
        pre_menu_03_over = newImage('images/menu_03-over.gif');
        pre_menu_04_over = newImage('images/menu_04-over.gif');
        pre_z_menu_02_over = newImage('images/z-menu_02-over.gif');
        pre_z_menu_03_over = newImage('images/z-menu_03-over.gif');
        preloadFlag = true;
    }
}
function changeImages() {
    changeImagesArray(changeImages.arguments);
}
function changeImagesArray(array) {
    if (preloadFlag == true) {
        var d = document; var img;
        for (i=0;i<array.length;i+=2) {
            img = null; var n = array[i];
            if (d.images) {
                if (d.layers) {img = findElement(n,0);}
                else {img = d.images[n];}
            }
            if (!img && d.getElementById) {img = d.getElementById(n);}
            if (!img && d.getElementsByName) {
                var elms = d.getElementsByName(n);
                if (elms) {
                    for (j=0;j<elms.length;j++) {
                        if (elms[j].src) {img = elms[j]; break;}
                    }
                }
            }
            if (img) {img.src = array[i+1];}
        }
    }
}
function newImage(arg) {
    if (document.images) {
        rslt = new Image();
        rslt.src = arg;
        return rslt;
    }
}