Just in case this might help someone else out.. If you know the container and tab that you want to output to you can do this:
By default there is only one container, though I think there may be addons that make other containers:
And the tabs seem to be numbered from left to right so the second tab would be 2:
Using those you can output 'Ta daaaaaaa' to the first container on the 2nd tab using the following:
Lua Code:
CHAT_SYSTEM.containers[containerNum].windows[tabNum].buffer:AddMessage('Ta daaaaaaa')
I'd be glad to know if someone comes up with a better solution than this.
~Zolan