Alright, here's one for the odd book. This is in an unmodded game, for the record. But it's real. I'm not crazy. I'm not.
Very rarely a kennel will fail to produce wargs. Speculation: I think it has something to do with the building finishing construction extremely quickly.
http://img52.imageshack.us/img52/6679/elemental1291953168.jpg
Note that the kennel is completed, and yet, turn after turn it does not produce wargs.
Opening the city hiergammemon lists the building, but note a lack of warg production
http://img31.imageshack.us/img31/2453/elemental1291953139.jpg
for comparison, this is how it should look:
http://img525.imageshack.us/img525/9718/elemental1291952993.jpg
Uploading a save is pointless, the bonus is re-assigned when I load a faulty game (believe it!). I don't know the steps to reproduce it.
For the sake of my own sanity, please increase the building time on the kennel to 2. And if not for my sanity, then for the flight of birds, and the prisoner.
Or fix the problem, heh.