dont know if it's IC specific or not
QuoteDisplay Morejava.util.ConcurrentModificationException
at java.util.HashMap$HashIterator.nextEntry(Unknown Source)
at java.util.HashMap$ValueIterator.next(Unknown Source)
at vy.a(Chunk.java:813)
at rv.a(World.java:2869)
at wt.a(NetClientHandler.java:420)
at rk.a(SourceFile:81)
at iq.b(SourceFile:272)
at wt.b(NetClientHandler.java:64)
at gx.c(SourceFile:57)
at net.minecraft.client.Minecraft.k(SourceFile:1388)
at net.minecraft.client.Minecraft.run(SourceFile:666)
at java.lang.Thread.run(Unknown Source)
Does not happen all the time!
Edit: Seems to happen when you run arround too