Is it possible to change your privatemessaging class:

In ANY way to make it check port as well to determine if the friend is online/offline?
Recently added two worlds (43594/5555) but I have no idea how to enable/make it so you can cross-world pm.

I understand it's a bad idea to run multiple servers on the same vps/server but for future reference (when I decide to go for an additional vps) I'd like to know how to multi-world pm.