Open Fatal error while connecting to server

Summary of the problem Fatal error while connecting to server

Pack Version 1.2

What is the bug? I own a FTB Revelation server and i used to play in 2 different FTB Revelation server and all the servers i played have the same problem. The problem is players starting to get Fatal Error while they are trying to connect the server.

Mod & Version

Link to log file

Is it repeatable?

Known Fix The only fix i can find was finding random a FTB Revelation v1.2 public server join it, leave it then try to join to my own server and it fix the problem but it's just
temporary fix..

 

http://paste.feed-the-beast.com/view/305161d5