function popup(url,width,height) {
    /*
    var width = 300;
    var height = 200;
    */
    var left = (screen.width - width) / 2;
    var top = (screen.height - height) / 2;
    var params = 'width=' + width + ', height=' + height + ', top=' + top + ', left=' + left +', directories=no, location=no, resizable=no';
    /*
    params += ', menubar=no';
    params += ', resizable=no';
    params += ', scrollbars=no';
    params += ', status=no';
    params += ', toolbar=no';
    */
    newwin = window.open(url, 'windowname5', params);
    if (window.focus) { newwin.focus() }
    return false;
}