Tekkit Crashes when my friend joins a server

Mattyboi6789 · 2013-05-26T20:59:43+0000

My friend try's joining a server, hes running 3.1.2 (Same as the server) When he try's to join my server, it says "Logging in" for about 5 seconds, then the screen goes black, then minecraft crashes comes up for like a second then a full white screen Does anyone know how to fix this or what might be causing it? He is running 64bit java.