code: public void renameValue(String oldValue, String newValue, Locale locale) throws CmsIllegalArgumentException {
  
          CmsXmlHtmlValue oldXmlHtmlValue = (CmsXmlHtmlValue)getValue(oldValue, locale);
          if (oldXmlHtmlValue == null) {
              throw new CmsIllegalArgumentException(
                  Messages.get().container(Messages.ERR_XML_PAGE_NO_ELEM_FOR_LANG_2, oldValue, locale));
          }
  
          if (hasValue(newValue, locale)) {
              throw new CmsIllegalArgumentException(
                  Messages.get().container(Messages.ERR_XML_PAGE_LANG_ELEM_EXISTS_2, newValue, locale));
          }
          if (newValue.indexOf('[') >= 0) {
              throw new CmsIllegalArgumentException(
                  Messages.get().container(Messages.ERR_XML_PAGE_CONTAINS_INDEX_1, newValue));
          }
  
          // get the element
          Element element = oldXmlHtmlValue.getElement();
  
          // update value of the element attribute 'NAME'
          element.addAttribute(ATTRIBUTE_NAME, newValue);
  
          // re-initialize the document to update the bookmarks
          initDocument(m_document, m_encoding, getContentDefinition());
      }
docs: Renames the page-element value from the old to the new one.<p>
  
  @param oldValue the old value
  @param newValue the new value
  @param locale the locale
  
  @throws CmsIllegalArgumentException if the name contains an index ("[&lt;number&gt;]"), the new value for the
  given locale already exists in the xmlpage or the the old value does not exist for the locale in the xmlpage.