function szokoev(year) {
	if ((2000-year)%4==0) { return true; } else { return false; }
}

function setnap(ev,ho,napobj) {
  napobj.length=0;
	  if (ho=='01' || ho=='03' || ho=='05' || ho=='07' || ho=='08' || ho=='10' || ho=='12') {
		  var napok=31;
	  }
	  if (ho=='04' || ho=='06' || ho=='09' || ho=='11') {
		  var napok=30;
	  }
	  if (ho=='02' && szokoev(ev)) {
		  var napok=29;
	  }
	  if (ho=='02' && !szokoev(ev)) {
		  var napok=28;
	  }

	  for(i=0;i<napok;i++) {
				if ((i+1)<10) {
					nap=new String('0'+(i+1));
					napobj.options[i]=new Option(nap,nap);
				} else {
					nap=new String(i+1);
					napobj.options[i]=new Option(nap,nap);
				} 
	  }
}

function noenter() {
	 if (window.event && window.event.keyCode == 13)  {
		 return false; 
     }
 }