Say, wasn't "claim territory" an option? Seems like I forgot to uncheck it, or I didn't see it in the options. (Build r685).
Had a scouting group get trapped by foreign territory, then while waiting for borders to auto-push that unit out I accidentally claimed the tile they were sitting on, and now I think they're stuck
View attachment 372887
Edit:
Also, did you guys revamp religions recently (I'm guessing after r680-r682)? I noticed the techs descriptions only mention founding a religion, not specific names. Was surprised when someone founded Islam early in the game, since previously it was something like the last to be founded. Nice touch, I like the randomness. On the other hand, it seems the AIs grab them pretty fast, in the 3 maps I rolled for r685 I've never managed once to found a religion, heh.