function popUp(pop_url, pop_width, pop_height) {
window_id = new Date().getTime();
eval("page" + window_id + " = window.open(pop_url, '" + window_id + "', 'toolbar=0,scrollbars=1,location=0,statusbar=0,menubar=0,resizable=0,width=" + pop_width + ",height=" + pop_height + "');");
}