updateChildRows = function(el) {
  var num = el.selectedIndex;
  var root_el = $('kinderen')
  var root_childs = root_el.childNodes
  var numChilds = root_childs.length;
  var cnum = '';
  root_el.innerHTML = ''
  for(var i=1;i<num+1;++i) {
    cnum = i
    if (i<10) {
      cnum = '&nbsp;&nbsp;'+i
    }
    root_el.innerHTML = root_el.innerHTML + '<input type="hidden" value="kind_'+i+'" name="ifields:list"/>';
    root_el.innerHTML = root_el.innerHTML + '<input type="hidden" value="'+i+'" name="tfields:list"/>';
    root_el.innerHTML = root_el.innerHTML + '<div class="title fleft">'+cnum+'</div>';
    root_el.innerHTML = root_el.innerHTML + '<input class="value_text" id="kind_'+i+'" name="kind_'+i+'" type="text"/>';
    root_el.innerHTML = root_el.innerHTML + '<div class="clear"></div>';
  }
  if (num > 0) {
    root_el.style.display = 'block';
  }
}