minecraft has crashed

Put the summary of the bug you're having here

------THE MINECRAFT VERSION IS 1.4.7 THE TOPIC DiDN'T LET ME CHOSE THIS ONE------

What I expected to happen was...:
Entering in my house the game crashed and i can't get out because it crashes immediatly when ever i log in again

What actually happened was...:
The game crashed

Steps to Reproduce:
1. enter in my house
2. the game was blocked
3. the game crashed