Localised Chat Channels

I am looking for a plugin that will do the following:

Local chat channels fixed to specified locations (perhaps using a MagicStick)
Automatic channel join when entering specified area
Default to global chat when not in a specified area
CraftBukkit compatible

Here's what I want to achieve:

I would like to create a room where Admins/Ops can go for private chat without snoopers being able to listen in.

I can set up a room and prevent access using iConomy Residence and LWC, but I can't implement the chat feature.

Alternatively, if the plugin was set to only allow certain permission groups to join the chat, and then automatically join them as they enter the room, then I can simply specifiy the location in the room I want and anyone else entering will not be able to join.

Does this plugin already exist as I can't see anything that QUITE does this on the forum.