Item frames falling

Put the summary of the bug you're having here

What I expected to happen was item frames staying on the walls
Describe what you thought should happen here

What actually happened was: Item frames fell off the walls
Describe what happened here

Steps to Reproduce:
1. Put an item frame with fire, portal or an arrow in it.
2. Wait some time (log out).
3. When you log in, the item frames might be dropped on the floor.