I have seen several instances of incorrectTV error messages saying "there are no movies (or music or TV shows etc.) in the library. This is totally BS as I have like almost 2TB of stuff on a streaming network connected Mini in the back of the house.
I have this when
tv times out waiting for the streaming server to respond. I have a similar setup to you, and receive this message when the external firewire drives on the Mini take a bit too long to spin up from sleep. The
tv gets bored waiting and claims that the streaming server has no content. Possibly 2.1 has a shorter timeout, or different behaviour in the timeout situation than earlier software releases?