Hopper: java.lang.NullPointerException

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-196471/

Crash:

java.lang.NullPointerException
	at afm.a(SourceFile:57)
	at afk.a(SourceFile:423)
	at ade.d(SourceFile:309)
	at akx.a(SourceFile:411)
	at akx.a(SourceFile:500)
	at akg.a(SourceFile:1534)
	at akz.a(SourceFile:37)
	at akr.a(SourceFile:88)
	at agn.a(SourceFile:401)
	at km.a(SourceFile:156)
	at afk.a(SourceFile:775)
	at km.c(SourceFile:93)
	at kl.<init>(SourceFile:28)
	at kk.a(SourceFile:209)
	at kk.d(SourceFile:343)
	at jh.d(SourceFile:211)
	at kv.a(SourceFile:270)
	at gn.a(SourceFile:136)
	at eb.b(SourceFile:63)
	at kv.e(SourceFile:64)

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

---- Minecraft Crash Report ----
// Who set us up the TNT?

Time: 20.09.13 15:59
Description: Ticking memory connection

java.lang.NullPointerException
	at afm.a(SourceFile:57)
	at afk.a(SourceFile:423)
	at ade.d(SourceFile:309)
	at akx.a(SourceFile:411)
	at akx.a(SourceFile:500)
	at akg.a(SourceFile:1534)
	at akz.a(SourceFile:37)
	at akr.a(SourceFile:88)
	at agn.a(SourceFile:401)
	at km.a(SourceFile:156)
	at afk.a(SourceFile:775)
	at km.c(SourceFile:93)
	at kl.<init>(SourceFile:28)
	at kk.a(SourceFile:209)
	at kk.d(SourceFile:343)
	at jh.d(SourceFile:211)
	at kv.a(SourceFile:270)
	at gn.a(SourceFile:136)
	at eb.b(SourceFile:63)
	at kv.e(SourceFile:64)
	at ky.b(SourceFile:37)
	at bow.b(SourceFile:83)
	at net.minecraft.server.MinecraftServer.u(SourceFile:487)
	at net.minecraft.server.MinecraftServer.t(SourceFile:404)
	at bot.t(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:338)
	at jc.run(SourceFile:581)


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

-- Head --
Stacktrace:
	at afm.a(SourceFile:57)
	at afk.a(SourceFile:423)
	at ade.d(SourceFile:309)
	at akx.a(SourceFile:411)
	at akx.a(SourceFile:500)
	at akg.a(SourceFile:1534)
	at akz.a(SourceFile:37)
	at akr.a(SourceFile:88)
	at agn.a(SourceFile:401)
	at km.a(SourceFile:156)
	at afk.a(SourceFile:775)
	at km.c(SourceFile:93)
	at kl.<init>(SourceFile:28)
	at kk.a(SourceFile:209)
	at kk.d(SourceFile:343)
	at jh.d(SourceFile:211)
	at kv.a(SourceFile:270)
	at gn.a(SourceFile:136)
	at eb.b(SourceFile:63)
	at kv.e(SourceFile:64)

-- Ticking connection --
Details:
	Connection: kv@b0e78a
Stacktrace:
	at ky.b(SourceFile:37)
	at bow.b(SourceFile:83)
	at net.minecraft.server.MinecraftServer.u(SourceFile:487)
	at net.minecraft.server.MinecraftServer.t(SourceFile:404)
	at bot.t(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:338)
	at jc.run(SourceFile:581)

-- System Details --
Details:
	Minecraft Version: 13w38b
	Operating System: Windows 7 (x86) version 6.1
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 183136040 bytes (174 MB) / 320745472 bytes (305 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 7806 (437136 bytes; 0 MB) allocated, 6586 (368816 bytes; 0 MB) used
	IntCache: cache: 1, tcache: 1, allocated: 12, tallocated: 94
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 1666 (93296 bytes; 0 MB) allocated, 1358 (76048 bytes; 0 MB) used
	Player Count: 1 / 8; [kq['macwojs'/448, l='troll', x=223,86, y=71,95, z=-394,90]]
	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-196471/12592657/