My question would be, why are you needing to do this often? Unless of course you're naming machines after people; a Bad Idea, as people move on, computers are switched, etc. Move to a consistent naming scheme and add your users' names to the Description field in the appropriate place in your network settings. If your boss objects, tell him how much time (=money) it costs the company for you to have to go through the renaming/rejoining process.