locked chest piston crash

Put the summary of the bug you're having here
crashed Redstone contraption
What I expected to happen was...:
Describe what you thought should happen here
should have suffocated me (although I was In creative)
What actually happened was...:
Describe what happened here
Crashed me
Steps to Reproduce:
1.put downwards facing sticky piston 3 block above ground
2. place locked chest (ID 95) under it
3.stand under locked chest and power piston with lever