code: private void _removeSubtreeClientId(String clientId)
    {
      // Loop through each entry in the map and check to see whether
      // the client id to remove should be contained in the corresponding
      // collection - ie. whether the key (the NamingContainer client id)
      // is present at the start of the client id to remove.
      for (String key : _subtreeClientIds.keySet())
      {
        if (clientId.startsWith(key))
        {
          // If the clientId starts with the key, we should
          // have an entry for this clientId in the corresponding
          // collection.  Remove it.
          Collection<String> ids = _subtreeClientIds.get(key);
          ids.remove(clientId);
        }
      }
    }
docs: entries from our subtree collections