Has this been fixed?
I've just had an issue that might be explained by this bug.
Following situation:
For some reason, the Russians thought it was a good idea to move an invasion army into the Adria. Naturallly, my fleets approached the visitor. It's a bizarre situation: Russias intentions are pretty obvious, but due to limited diplomacy, I can't do more than move fleets and armies into the vicinity.
Okay, so for one turn, nothing happens. Peace, and his fleet remains inside my containment.
Next round, however, he declares war and moves some land armies in the east. Meanwhile, the invasion fleet does nothing. He doesn't even try to land his troops before I would sink the fleet in my next turn.
So my next turn starts, I attack and sink the smaller enemy fleet. His invasion army on the ships was actually more powerful than my land army at the coast, so by quickly putting his army to the shore, he might have at least saved his troops. But this is not the actual problem, it's just the usual dumb AI behavior.
The actual problem:
I can't say if the intercept ability would have worked if the AI had tried to actually land his army. I hope it would have, as this is the only possibility to defend your shores against invasions during peace time!!
Okay, but there's another thing: I loaded the game and moved one fleet slightly to the south. This apparently gave them enough space to sail away, which they did right after declaring war on me. They approached another, smaller fleet of mine some distance away, but my two large blockade fleets weren't able to intercept his move. Clearly a bug.