Is There A Seperate World Chat Plugin?

Is it possibe to have a World Chat where:

- You Can only Chat with the World You are on
- No one in the Other World Can Hear You Talking in Your World

Its like having 2 Servers in 1.

I'm running a Build and RPG Map in my server, different maps for each. I just don't people in the Build Map to Hear People in the RPG Map.

Wouldn't it be weird if You're Hardcore RPGing and someone said... "Hey.. Got any Stone?"