function definewindow()
{
  siWin = window.open("", "siWinName","scrollbars,resizable,width=600,height=400");
}
function openwindow(u)
{
  definewindow()
  if (u.indexOf('?')>0)
    u = u + '&'
  else
    u = u + '?'
  u = u + "Fuzz=" + Math.round(1000*Math.random());
  siWin.location.href = u;
  siWin.focus();
}
function closewindow()
{
  definewindow()
  if (siWin.closed == false)
    siWin.close();
}