function switchLangGroup(instancename, lang, languages, editors)
{
  var tables = document.getElementsByTagName("table");
  for (i=0; i<tables.length; i++) {
      if (tables[i].className == "form_table") {
          var rows = tables[i].getElementsByTagName("tr");
          for (j=0; j<rows.length; j++) {
              if (rows[j].className == instancename+"_langgroup_"+lang) {
                  rows[j].style.display = "";
              } else if (rows[j].className &&
                         rows[j].className.indexOf(instancename+"_langgroup_") == 0) {
                  rows[j].style.display = "none";
              }
          }
      }
  }
  
  // This is a hack for Gecko... it stops editing when the editor is hidden.
  // http://wiki.fckeditor.net/Troubleshooting#head-b3157703eeeef9d287b4c922f9b43eab9d551417
  if (!document.all) {
      for (i=0; i<editors.length; i++) {
          var editor = FCKeditorAPI.GetInstance(editors[i]);
          if (editor.EditMode == FCK_EDITMODE_WYSIWYG) {
              editor.MakeEditable();
          }
      }
  }
  
  for (i=0; i<languages.length; i++) {
      if (languages[i] == lang) {
            document.getElementById(instancename+"_langgrouplink_"+lang).className = "form_langswitch_selected";
      } else {
          document.getElementById(instancename+"_langgrouplink_"+languages[i]).className = "";
      }
  }
}