Would ppear that the servers are running the wrong version of the game, need a sysadmin or someone who can access the server box to take a look, and to maybe add the tag "NRNS" to the servers info so it can be filtered, as Source Engine filters by tags, like things on the server, to find them.
Trying to figure out wht we're running right now on it but no idea, help would be nice, sitting in TF2 channel right now, if someone has time.
