Hopper: java.lang.NullPointerException: Ticking entity

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-434661/

Crash:

java.lang.NullPointerException: Ticking entity
	at vu.a(SourceFile:133)
	at vu.k(SourceFile:120)
	at vu.h(SourceFile:95)
	at afl.a(SourceFile:1368)
	at mj.a(SourceFile:480)
	at afl.g(SourceFile:1346)

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

---- Minecraft Crash Report ----
// Ouch. That hurt :(

Time: 21.10.13 18:57
Description: Ticking entity

java.lang.NullPointerException: Ticking entity
	at vu.a(SourceFile:133)
	at vu.k(SourceFile:120)
	at vu.h(SourceFile:95)
	at afl.a(SourceFile:1368)
	at mj.a(SourceFile:480)
	at afl.g(SourceFile:1346)
	at afl.h(SourceFile:1253)
	at mj.h(SourceFile:365)
	at net.minecraft.server.MinecraftServer.u(SourceFile:511)
	at net.minecraft.server.MinecraftServer.t(SourceFile:441)
	at bsg.t(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:358)
	at ky.run(SourceFile:617)


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

-- Head --
Stacktrace:
	at vu.a(SourceFile:133)
	at vu.k(SourceFile:120)
	at vu.h(SourceFile:95)
	at afl.a(SourceFile:1368)
	at mj.a(SourceFile:480)
	at afl.g(SourceFile:1346)

-- Entity being ticked --
Details:
	Entity Type: Item (vu)
	Entity ID: 18136
	Entity Name: ~~ERROR~~ NullPointerException: null
	Entity's Exact location: 438,33, 69,13, -463,88
	Entity's Block location: World: (438,69,-464), Chunk: (at 6,4,0 in 27,-29; contains blocks 432,0,-464 to 447,255,-449), Region: (0,-1; contains chunks 0,-32 to 31,-1, blocks 0,0,-512 to 511,255,-1)
	Entity's Momentum: 0,00, 0,00, 0,00
Stacktrace:
	at afl.h(SourceFile:1253)
	at mj.h(SourceFile:365)

-- Affected level --
Details:
	Level name: sone sdr
	All players: 1 total; [mm['sabs20000'/203, l='sone sdr', x=438,02, y=75,89, z=-459,57]]
	Chunk stats: ServerChunkCache: 1067 Drop: 0
	Level seed: 1667704446586757485
	Level generator: ID 00 - default, ver 1. Features enabled: true
	Level generator options: 
	Level spawn location: World: (24,64,256), Chunk: (at 8,4,0 in 1,16; contains blocks 16,0,256 to 31,255,271), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 574553 game time, 3153 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 11769 (now: false), thunder time: 78218 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: true
Stacktrace:
	at net.minecraft.server.MinecraftServer.u(SourceFile:511)
	at net.minecraft.server.MinecraftServer.t(SourceFile:441)
	at bsg.t(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:358)
	at ky.run(SourceFile:617)

-- System Details --
Details:
	Minecraft Version: 13w43a
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 159958616 bytes (152 MB) / 461701120 bytes (440 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	AABB Pool Size: 6783 (379848 bytes; 0 MB) allocated, 6437 (360472 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 6350 (355600 bytes; 0 MB) allocated, 6120 (342720 bytes; 0 MB) used
	Player Count: 1 / 8; [mm['sabs20000'/203, l='sone sdr', x=438,02, y=75,89, z=-459,57]]
	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-434661/20341214/