function popitup(mypage,myname,w,h,scroll){
    scroll=1;
    w=820;
    h=620;
    LeftPosition = (screen.width) ? (screen.width-w)/2 : 0;
    TopPosition = (screen.height) ? (screen.height-h)/2 : 0;
    settings = 'height='+h+',width='+w+',top='+TopPosition+',left='+LeftPosition+',scrollbars='+scroll+',resizable=false';
    win = window.open(mypage,myname,settings);
    return false;
}