var win = null;

function NewWindow(mypage,myname,w,h)
{
    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=no,resizable=no,status=no'
    win = window.open(mypage,myname,settings)
}