function pop(name, url, width, height)
{
    wleft = (screen.width - width) / 2;
    wtop = (screen.height - height) / 2;
    window.open(url, name, 'height=' + height + 'px,width=' + width + 'px,left=' + wleft + 'px,top=' + wtop + 'px,location=no,menubar=no,scrollbars=1,resizable=no,help=no,status=no');
}

function pop1(name, url, width, height)
{
    wleft = (screen.width - width) / 2;
    wtop = (screen.height - height) / 2;
    window.open(url, name, 'height=' + height + 'px,width=' + width + 'px,left=' + wleft + 'px,top=' + wtop + 'px,location=no,menubar=no,scrollbars=no,resizable=no,help=no,status=no');
}

function pop2(name, url, width, height)
{
    if(window.showModalDialog)
        window.showModalDialog(url, window, 'dialogHeight=' + height + 'px;dialogWidth=' + width + 'px;resizable=no;help=no;status=no;');
    else
        pop1(name, url, width, height);
}