Thread Safety of log4net

According to this link, RollingFileAppender is thread safe (as far as logging is concerned). This is coming from one of the developers of log4net. He specifically says that locking like this is not required in your code:

lock(logger)
{
  logger.Info("Hello!");
}

Straight from the log4net FAQ:

Is log4net thread-safe?

Yes, log4net is thread-safe.

So, no need for manual locking.