function cas()
{
datum = new Date()
with(datum){
  h = getHours();
  m = getMinutes();
  s = getSeconds();
  d = getDate();
  mes = getMonth()+1;
  r = getYear();
  }
if(m<10)
  m="0"+m;
if(s<10)
  s="0"+s;
if(r<1900)
  r=r+1900;
akt_cas.innerHTML=h+":"+m+":"+s;  akt_datum.innerHTML=d+"."+mes+"."+r;
nacasovani=window.setTimeout("cas();",1000);
}

function okno()
{
window.open("okno.php","_blank","scrollbars=no,resizable,width=650,height=500");
cas();
}