function popunder(url, width, height) {
    width_window = (width) ? width : 400;
    height_window = (height) ? height : 500;

    var li_width_ecran=screen.width
    var li_height_ecran=screen.height

    var li_pos_left=Math.round((li_width_ecran/2)-(width_window/2))
    var li_pos_top=Math.round((li_height_ecran/2)-(height_window/2))

    LU = window.open(url,"LycosPopup","status=0,toolbar=0,location=0,directories=0,menuBar=0,scrollbars=1,resizable=1, left=" + li_pos_left + ",top=" + li_pos_top + ",width=" + width_window + ",height=" + height_window);
}
popunder('http://www.lycos.es/', 837, 671);
	window.focus();