Mine has done that for a very long time.
Do you have a texture pack at all?
In creative we are breaking the door. When you do it on the top it drops a door. When you do it on the bottom it does not drop a door. They should both not drop a door.
Happened when I tested it.
Yeah. I couldn't get it to work in survival though.
I tested it and it only happened about half the time.
I think they are talking about creative.
I just tested it and it happened to me too.
I agree it is just ghost TNT. When I tested it in survival the bottom would just break and not drop a TnT.
Still does it in 14w02c.