[0.95.20] Turrets on defensive walls can't hit targets

[ekhymosis]

So I have three people manning the turrets on my walls and for the past 3 real life minutes, they have not been able to hit the last two river raptors. They keep aiming just above the raptors. The walls and floors near the raptors are full of arrows but not a single one has hit these raptors. This behavior has been going on since .93 if I recall correctly. Why is this?