var dom = document.getElementById ? 1 : 0;
function getObject(id) {
    var obj;
    if (dom) {
        obj = document.getElementById(id);
    } else {
        obj = document.all[id];
    }
    return obj;
}

function activateMenuItem(obj) {
    obj.className = "active_menu";
    obj.style.cursor = "Hand";
    var image = getObject('logo_lamp');
    image.src="images/logo_lamp_active.gif";
}

function deactivateMenuItem(obj) {
    obj.className = "menu";
    obj.style.cursor = "Default";
    var image = getObject('logo_lamp');
    image.src="images/logo_lamp.gif";
}