function openWindow(url,windowName,width,height){
    var x = parseInt(screen.width / 2.0) - (width / 2.0);
    var y = parseInt(screen.height / 2.0) - (height / 2.0);
    var isMSIE= (navigator.appName == "Microsoft Internet Explorer");
    if (isMSIE) {
        var p = "resizable=1,location=no,scrollbars=no,width=";
        p = p+width;
           p = p+",height=";
           p = p+height;
        p = p+",left=";
        p = p+x;
        p = p+",top=";
        p = p+y;
        retval = window.open(url, windowName, p);
    } else {
        var win = window.open(url, "ZyiisPopup", "top=" + y + ",left=" + x + ",scrollbars=" + scrollbars + ",dialog=yes,modal=yes,width=" + width + ",height=" + height + ",resizable=no" );
        eval("try { win.resizeTo(width, height); } catch(e) { }");
        win.focus();
    }
}