function openPopup(url, name, width, height)
{
    var left           = parseInt((screen.availWidth/2) - (width/2));
    var top            = parseInt((screen.availHeight/2) - (height/2));
    var windowFeatures = "width=" + width + ",height=" + height + ",status,resizable,left=" + left + ",top=" + top + "screenX=" + left + ",screenY=" + top;
    window.open(url, name, windowFeatures);
}