code: public static void setLogStdErr(boolean log)
      {
          if (log)
          {
              if (!(System.err instanceof LogStream))
                  System.setErr(new LogStream.STDERR());
          }
          else
              System.setErr(STDERR_STREAM);
      }
docs: Log standard error stream.
  If set to true, output to stderr will be directed to an instance
  of LogStream and logged.  Beware of log loops from logs that write to stderr.