Get killed then game crashes

Put the summary of the bug you're having here

What I expected to happen was...:
Describe what you thought should happen here

What actually happened was...:
I was playing on the Nexus (thenexusmc.net) and when i was killed my game just crashed.

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. Go to to the nexus and capture the flag on 1.7.2 or 1.7.4
3. Get killed and i will crash - It happens with me and when i play on different minecraft servers when i die my game dosen`t crash