docs: @Nonnull
    public static EChange setTimeoutMilliSecs (final long nMilliSecs)
    {
      return s_aRWLock.writeLocked ( () -> {
        if (s_nTimeoutMilliSecs == nMilliSecs)
          return EChange.UNCHANGED;
        if (nMilliSecs <= 0)
          LOGGER.warn ("You are setting an indefinite socket timeout for the mail transport api: " + nMilliSecs);
        s_nTimeoutMilliSecs = nMilliSecs;
        return EChange.CHANGED;
      });
    }