Chest on Horse crash

I used NBTExplorer to put a chest in a horse. It sorta worked. And sorta didn't.

What I expected to happen was...:
I thought would happen is nothing actually.

What actually happened was...:
I log in and the horse did in fact have the chests on him like a donkey/mule does. But clicking on the horse with anything (right clicking) just closes the game without a crash message. I know you aren't supposed to put chests on horses. But if this is fixed it would be a nice thing for adventure map makers.

Steps to Reproduce:
1. Open NBTExplorer and search Horse whilst clicked on your snapshot 13w21a world. (Remember to put a horse in the world. 1 is recommended)
2. Click on ChestedHorse and edit it with the pencil icon and edit it to 1
3. Log in your world and find the horse you editted. Now right click the horse.