function bg_roll(elementID, img_url) {
    var theElement = document.getElementById(elementID);
    theElement.style.backgroundImage = "url(" + img_url + ")";
}

function img_roll(elementID, img_url) {
    var theElement = document.getElementById(elementID);
    theElement.src = img_url;
}

// preload rollovers
if (document.images) {
    pic1 = new Image(227, 27);
    pic1.src = "layout_images/sideNavItemSingleLineSelected.png";

    pic2 = new Image(227, 49);
    pic2.src = "layout_images/sideNavItemDoubleLineSelected.png";

    pic3 = new Image(64, 28);
    pic3.src = "layout_images/memberButtonItem_depressed.png";

    pic4 = new Image(64, 28);
    pic4.src = "layout_images/memberButtonItem_selected.png";
}