//preloading images

        home_on = new Image();
        home_on.src = "/images/n_sub_home1.gif";
        home_off = new Image();
        home_off.src = "/images/n_sub_home0.gif";

        about_on = new Image();
        about_on.src = "/images/n_sub_about1.gif";
        about_off = new Image();
        about_off.src = "/images/n_sub_about0.gif";

        board_on = new Image();
        board_on.src = "/images/n_sub_board1.gif";
        board_off = new Image();
        board_off.src = "/images/n_sub_board0.gif";

        photos_on = new Image();
        photos_on.src = "/images/n_sub_photos1.gif";
        photos_off = new Image();
        photos_off.src = "/images/n_sub_photos0.gif";

        gear_on = new Image();
        gear_on.src = "/images/n_sub_gear1.gif";
        gear_off = new Image();
        gear_off.src = "/images/n_sub_gear0.gif";

        links_on = new Image();
        links_on.src = "/images/n_sub_links1.gif";
        links_off = new Image();
        links_off.src = "/images/n_sub_links0.gif";

        contact_on = new Image();
        contact_on.src = "/images/n_sub_contact1.gif";
        contact_off = new Image();
        contact_off.src = "/images/n_sub_contact0.gif";