<!-- thx a lot: http://wiki.wmii.pl/wiki/Moduly_strony_w_zakladkach :* :*~ --!>
function changeToTab(link_element, tab_name) {
    changeCurrentTabLink(link_element);
    changeCurrentTabContent(tab_name);
  }
 
  function changeCurrentTabContent(tab_name) {
    var tab_elements = document.getElementById('tabs').getElementsByTagName('div')[1].getElementsByTagName('div');
    for (var i = 0; i < tab_elements.length; i++) {
      if (tab_elements[i].className == 'content_tab') {
        tab_elements[i].style.display = 'none';
      }
    }
    document.getElementById(tab_name).style.display = 'block';
  }
 
  function changeCurrentTabLink(link_element) {
    var tab_elements = document.getElementById('tabs').getElementsByTagName('ul')[0].getElementsByTagName('li');
    for (var i = 0; i < tab_elements.length; i++) {
      tab_elements[i].getElementsByTagName('a')[0].className = '';
    }
    link_element.className = 'current';
  }