I get the same error when using the RMI transport. I get it every 60 seconds which I believe is based on one of the timeouts in the config. It does not seem to create a problem with my remoting which works alright. But, of course I don't want to assume it's a non-issue. I too saw someone on one of the forums trying to change the logging to hide this error which seems the same as sweeping it under the rug ;-)
Additionaly, when I use other transports such as HTTP or Socket I don't get the error. I would also be interested if anyone knows what's causing this, whether it's a problem and if there's a way to fix it.