on 1.7.7-8-9 When i join a server i get thrown out and get a crash report, but i can play on 1.8

Put the summary of the bug you're having here

*What I expected to happen was...: Joining the server
Describe what you thought should happen here
Joining the server
*What actually happened was...:kicked out and get a crash report
Describe what happened here
I was kicked out and got a crash report

Steps to Reproduce:
1. Start 1.7-8-9
2. ... join a server
3. ...get kicked out