Infinite Doors Glitch

On Jan. 30, 2013, when the update for v0.6.0 came out, I was playing survival mode in a world adjusting my door. I then broke the door (bottom part) so I could move it. Suddenly, 2 doors dropped instead of 1!

What I expected to happen was...
I thought that when I break the door, it would drop 1 door as usual.

What actually happened was...:
When I broke the door, 2 doors dropped.

Steps to Reproduce:
1. Craft a Wooden Door.
2. Place the Wooden Door (anywhere will work).
3. Break the Wooden Door on the bottom part (with hand or item in hand). You will notice that 2 Wooden Doors drop. Repeating this will probably give you infinite doors.