Null pointer Exeption -- Ticking block entity -- ticking tile.bedrock

[ultrasn0w]

Hey there,
My Minecraft sometimes crashes (once every 3 or 4 hours) and the log spits out this:
http://pastebin.com/RRKAye32
A Chunkloader is indeed placed on the Server, however the crash is clientside and far away from my position.

Greetings
ultrasn0w