code: private String _getIdFromClientId(String clientId)
    {
      final char separator = getFacesContext().getNamingContainerSeparatorChar();
      int lastIndex = clientId.lastIndexOf(separator);
  
      String id = null;
  
      if (lastIndex < 0)
      {
        id = clientId;
      }
      else if (lastIndex < (clientId.length() - 1))
      {
        id = clientId.substring(lastIndex + 1);              
      }
      //else
      //{
        // TODO log warning for trailing colon case
      //}
   
      return id;
    }
docs: out the trailing id segmetn.