They also seem to be invisible to other players and I've seen oak doors affected as well. MC-87474 talks about this.
Seems to work fine in 15w35b with spruce doors for me. I have villagers spawning in a villager farm (creative single player) with spruce doors only.
Ivan Sliouniaev
They also seem to be invisible to other players and I've seen oak doors affected as well. MC-87474 talks about this.