Hopper: java.lang.NullPointerException

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-191713/

Crash:

java.lang.NullPointerException
	at acs.a(SourceFile:55)
	at vb.a(SourceFile:291)
	at wz.a(SourceFile:59)
	at vx.a(SourceFile:238)
	at ku.a(SourceFile:647)
	at fm.a(SourceFile:32)
	at ea.b(SourceFile:64)
	at ku.e(SourceFile:63)

The following is the first clean report made public about this crash:

---- Minecraft Crash Report ----
// This doesn't make any sense!

Time: 9/19/13 8:12 PM
Description: Ticking memory connection

java.lang.NullPointerException
	at acs.a(SourceFile:55)
	at vb.a(SourceFile:291)
	at wz.a(SourceFile:59)
	at vx.a(SourceFile:238)
	at ku.a(SourceFile:647)
	at fm.a(SourceFile:32)
	at ea.b(SourceFile:64)
	at ku.e(SourceFile:63)
	at kx.b(SourceFile:37)
	at bou.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.u(SourceFile:487)
	at net.minecraft.server.MinecraftServer.t(SourceFile:404)
	at bor.t(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:338)
	at jb.run(SourceFile:581)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at acs.a(SourceFile:55)
	at vb.a(SourceFile:291)
	at wz.a(SourceFile:59)
	at vx.a(SourceFile:238)
	at ku.a(SourceFile:647)
	at fm.a(SourceFile:32)
	at ea.b(SourceFile:64)
	at ku.e(SourceFile:63)

-- Ticking connection --
Details:
	Connection: ku@6f01ba6f
Stacktrace:
	at kx.b(SourceFile:37)
	at bou.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.u(SourceFile:487)
	at net.minecraft.server.MinecraftServer.t(SourceFile:404)
	at bor.t(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:338)
	at jb.run(SourceFile:581)

-- System Details --
Details:
	Minecraft Version: 13w38a
	Operating System: Mac OS X (x86_64) version 10.8.5
	Java Version: 1.6.0_51, Apple Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
	Memory: 79072848 bytes (75 MB) / 215207936 bytes (205 MB) up to 1065025536 bytes (1015 MB)
	JVM Flags: 1 total; -Xmx1G
	AABB Pool Size: 732 (40992 bytes; 0 MB) allocated, 174 (9744 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 19176 (1073856 bytes; 1 MB) allocated, 61 (3416 bytes; 0 MB) used
	Player Count: 1 / 8; [kp['Cirelon'/2, l='§cHerobrine's Return §rby §bHypixel', x=-2185.91, y=48.00, z=899.66]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-191713/12416004/