private void readObject(@Nonnull final ObjectInputStream aOIS)
        throws IOException, ClassNotFoundException {
      aOIS.defaultReadObject();

      // Resolve user ID
      if (m_sUserID != null) {
        m_aUser = PhotonSecurityManager.getUserMgr().getUserOfID(m_sUserID);
        if (m_aUser == null)
          throw new IllegalStateException("Failed to resolve user with ID '" + m_sUserID + "'");
      }

      // Resolve manager
      m_aOwningMgr = LoggedInUserManager.getInstance();
    }