var show_time=false;
  var timerID=null;

  function stop(){
     if (show_time){
         clearTimeout(timerID);
         document.clock.date_time.value=" ";
     }
     show_time=false;
  }

  function start(form){
     var today=new Date();

     var display_value = "   " + today.getDate() + "."  +
        (today.getMonth()+1) + "." + today.getYear();


     display_value +="   " + today.getHours()
     if(today.getMinutes() < 10){
        display_value+=":0" + today.getMinutes();
     }
     else{
        display_value+=":" + today.getMinutes();
     }
     if (today.getSeconds() < 10){
        display_value+=":0" + today.getSeconds();
     }
     else{
        display_value+=":" + today.getSeconds();
     }
     if(today.getHours()>=12){
        display_value+="  "
        /* Here we have a variable called mygreeting where
           you can store somthing like this:
           mygreeting ="Good Morning!"; */
     }
     else{
        display_value+="  "
        /* Now set mygreeting to:
           mygreeting ="Good Afternoon!"; */
     }
        document.clock.date_time.value=display_value;
        timerID=setTimeout("start()",100);
        show_time=true;
        /* Here have an alert() method do the following:
           alert(mygreeting); */
  }