My mumble users sometimes wish there would be a way to be join & be in a channel, without no-one else outside of the channel knowing that they have actually connected to the server and are currently online.

Another mumble-service in another port would probably do the job, but it would create too big of a feeling of "inside circle only" which is not a nice thing in our friendship.
Privacy is needed only sometimes, when just want to relax with one friend, without interruption from others.

Perhaps a "secret, invite-only temporary channel" ? But the "user connected" should not be visible.
I don't know.
Ideas?
Maybe there is a solution that i'm not seeing.