Fire bug

Put the summary of the bug you're having here
When I get on my world it is in flames
What I expected to happen was...:
Describe what you thought should happen here
My world would not be on fire
What actually happened was...:
Describe what happened here
My world was in flames
Steps to Reproduce:
1. Build a wooden house
2. Put a 3 by 3 cobblestone cube with lava in the middle in the house
3. Watch the house be destroyed