function pop(url) {

    var winwidth = 450; // width of the new window
    var winheight = 290; // height of the new window
    var winleft = 100;
    var wintop = 250;

/*    if(parseInt(navigator.appVersion)>=4) {

        winleft = (screen.width / 2) - (winwidth / 2); // center the window right to left
        wintop = (screen.height / 2) - (winheight / 2); // center the window top to bottom

    }*/

    var attrib =  'top=' + wintop + ',left=' + winleft + ',height=' + winheight + ',width=' + winwidth + ',scrollbars=no, resizable=no';

    window.open(url, "PopUp", attrib);
    return void(null);

}