Need help with amount of players show on server list

Hi, I own 6 hunger game servers. The problem I'm having is that each server right now is set to 80 players each. I have one of the servers on a server list. So on that list it says 80/80 online when full. Well I have 6 servers and want to know how to make it combine the total number of players from 1. So instead of saying 80/80 full it'll say 80/480.

Another example:
This is the server list and this is my server
a.themchgames.com 80/80 players online

Well server b.themchgames.com, c.themchgames.com, d.themchgames.com, and e.themchgames.com are all alone. I want to take there players online and max player cap and combine it with server a so it's all one big server. I've seen servers do this before especially mcpvp ect. Can someone please please help me :S

Is there a bukkit plugin for this?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.