I crash when I try to join multiplayer servers.

Put the summary of the bug you're having here

*What I expected to happen was...:I tried to join my friends bukkit server on 1.7.9 and it crashes whe nI try to join.
Describe what you thought should happen here
by the way, the "Affects/Versions thing won't let me choose 1.7.9 So I HAVE to put 1.8.7
What actually happened was...:
Describe what happened here

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...I click on the server
3. ...It crashes