function Monat()
{
var nui = new Date();
var monat = nui.getMonth();
var monatsname;
 if (monat == 0) {monatsname = "Jan";}
 if (monat == 1) {monatsname = "Feb";}
 if (monat == 2) {monatsname = "Mar";}
 if (monat == 3) {monatsname = "Apr";}
 if (monat == 4) {monatsname = "Mai";}
 if (monat == 5) {monatsname = "Jun";}
 if (monat == 6) {monatsname = "Jul";}
 if (monat == 7) {monatsname = "Aug";}
 if (monat == 8) {monatsname = "Sep";}
 if (monat == 9) {monatsname = "Okt";}
 if (monat == 10) {monatsname = "Nov";}
 if (monat == 11) {monatsname = "Dec";}

var nur = new Date();
var datum = nur.getDate();
var Tag;
if(datum < 10) {Tag="0" + datum;}
else {Tag=datum;}

var nun = new Date();
var jahr = nun.getFullYear();

var std = new Date();
var hour = std.getHours();
var Uhrzeith;
if(hour < 10) {Uhrzeith="0" + hour;}
else {Uhrzeith=hour;}

var min = new Date();
var mint = min.getMinutes();
var Uhrzeitm;
if(mint < 10) {Uhrzeitm="0" + mint;}
else {Uhrzeitm=mint;}

var sec = new Date();
var sek = sec.getSeconds();
var Uhrzeits;
if(sek < 10) {Uhrzeits="0" + sek;}
else {Uhrzeits=sek;}

document.write(Tag+"."+monatsname+"."+jahr+" "+Uhrzeith+":"+Uhrzeitm+":"+Uhrzeits+" "+"Uhr");

window.setTimeout("",1000);
}

  <td valign=top height=24 width=142 rowspan=2>
  <p class=uhr><script language="JavaScript">Monat();</script></p>
  </td>