// enter page navigation rollover
function enterNavOver(over) {
    document.rollover_image.src = "enter_on_" + over + ".gif";
}

// enter page navigation rollout
function enterNavOut() {
    document.rollover_image.src = "enter_off.gif";
}

// preload rollover images
top_over_1 = new Image();
top_over_1.src = "enter_off.gif";
top_over_2 = new Image();
top_over_2.src = "enter_on_html.gif";
top_over_3 = new Image();
top_over_3.src = "enter_on_flash.gif";
top_over_4 = new Image();
top_over_4.src = "enter_on_download.gif";
top_over_5 = new Image();
top_over_5.src = "enter_on_choose.gif";