Sorry, posted before I saw your Last post.
Anyway, it appears that it's either Malfador made it so that you could never subjugate neutral empires or this really is a bug. I tried sending a treaty from either side, and both ended up with the Primean Federation (the galaxy's dominant empire in terms of ships, resources and score) being subjugated to the Bobroba States.
[ October 14, 2002, 15:01: Message edited by: Sandstig ]