Before the first caravan came, I had placed some cage traps--unaware of the bug where diplomats would trigger traps. The liason was caged, and even though she was released (via a lever) in a moderately timely fashion, she went insane and left unhappy, babbling and stripping as she walked off the map.
The next time the caravan came, she was still the liason. It must be hard to get fired from dwarven government jobs. In this case, though, I don't think she'll be back a third time...
Important: If the movie appears blank or fails to play it is because it was recorded using a corrupt version of Dwarf Fortress. This is a known bug and is reported in the tracker, bug 2489. The DFMA administration is in the process of cleaning up these movies from the site; and hopes bay12games will fix the game functionality soon.