I just captured an enemy colony with zero population in a simultaneous game. I remember this not being possible a while back, but decided to try it anyway. I didn't do anything special with my "caputure planet" fleet, but it did work. I wonder when this was fixed??
Strange. I don't see anything about it in the history.txt file. There was something else that came up on the forum recently that apparently was also fixed without an entry in history.txt either; can't remember exactly what it was right now.