Hopper: java.lang.ArrayIndexOutOfBoundsException

java.lang.ArrayIndexOutOfBoundsException
	at java.lang.System.arraycopy(Native Method)
	at adr.a(SourceFile:823)
	at bcw.a(SourceFile:927)
	at el.a(SourceFile:141)
	at cn.b(SourceFile:64)
	at bcw.e(SourceFile:98)

---- Minecraft Crash Report ----
// Surprise! Haha. Well, this is awkward.

Time: 19/09/13 18:34
Description: Exception in world tick

java.lang.ArrayIndexOutOfBoundsException
	at java.lang.System.arraycopy(Native Method)
	at adr.a(SourceFile:823)
	at bcw.a(SourceFile:927)
	at el.a(SourceFile:141)
	at cn.b(SourceFile:64)
	at bcw.e(SourceFile:98)
	at bdd.b(SourceFile:60)
	at atv.k(SourceFile:1386)
	at atv.S(SourceFile:663)
	at atv.d(SourceFile:619)
	at net.minecraft.client.main.Main.main(SourceFile:101)


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

-- Head --
Stacktrace:
	at java.lang.System.arraycopy(Native Method)
	at adr.a(SourceFile:823)
	at bcw.a(SourceFile:927)
	at el.a(SourceFile:141)
	at cn.b(SourceFile:64)
	at bcw.e(SourceFile:98)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bdi['hoskyg4'/35, l='MpServer', x=-91.31, y=74.81, z=-80.40]]
	Chunk stats: MultiplayerChunkCache: 389
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (-97,64,-86), Chunk: (at 15,4,10 in -7,-6; contains blocks -112,0,-96 to -97,255,-81), Region: (-1,-1; contains chunks -32,-32 to -1,-1, blocks -512,0,-512 to -1,255,-1)
	Level time: 50644 game time, 50644 day time
	Level dimension: 0
	Level storage version: 0x00000 - Unknown?
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
	Forced entities: 13 total; [ro['Bat'/32, l='MpServer', x=-43.25, y=17.95, z=-50.91], bdi['hoskyg4'/35, l='MpServer', x=-91.31, y=74.81, z=-80.40], sc['Squid'/11, l='MpServer', x=-125.18, y=50.31, z=-56.54], ro['Bat'/12, l='MpServer', x=-110.53, y=25.73, z=-3.28], ro['Bat'/15, l='MpServer', x=-107.97, y=33.51, z=-154.13], ro['Bat'/16, l='MpServer', x=-109.56, y=25.82, z=-2.09], ro['Bat'/21, l='MpServer', x=-86.19, y=29.24, z=-157.09], sc['Squid'/23, l='MpServer', x=-83.47, y=53.28, z=-56.47], ro['Bat'/22, l='MpServer', x=-94.28, y=12.05, z=-139.31], sc['Squid'/24, l='MpServer', x=-85.05, y=55.89, z=-36.33], ro['Bat'/29, l='MpServer', x=-59.06, y=39.14, z=-148.78], ro['Bat'/28, l='MpServer', x=-75.20, y=34.01, z=-159.13], ro['Bat'/30, l='MpServer', x=-55.34, y=17.00, z=-52.72]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bdd.a(SourceFile:284)
	at atv.k(SourceFile:1393)
	at atv.S(SourceFile:663)
	at atv.d(SourceFile:619)
	at net.minecraft.client.main.Main.main(SourceFile:101)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bdi['hoskyg4'/35, l='MpServer', x=-91.31, y=74.81, z=-80.40]]
	Chunk stats: MultiplayerChunkCache: 389
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (-97,64,-86), Chunk: (at 15,4,10 in -7,-6; contains blocks -112,0,-96 to -97,255,-81), Region: (-1,-1; contains chunks -32,-32 to -1,-1, blocks -512,0,-512 to -1,255,-1)
	Level time: 50644 game time, 50644 day time
	Level dimension: 0
	Level storage version: 0x00000 - Unknown?
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
	Forced entities: 13 total; [ro['Bat'/32, l='MpServer', x=-43.25, y=17.95, z=-50.91], bdi['hoskyg4'/35, l='MpServer', x=-91.31, y=74.81, z=-80.40], sc['Squid'/11, l='MpServer', x=-125.18, y=50.31, z=-56.54], ro['Bat'/12, l='MpServer', x=-110.53, y=25.73, z=-3.28], ro['Bat'/15, l='MpServer', x=-107.97, y=33.51, z=-154.13], ro['Bat'/16, l='MpServer', x=-109.56, y=25.82, z=-2.09], ro['Bat'/21, l='MpServer', x=-86.19, y=29.24, z=-157.09], sc['Squid'/23, l='MpServer', x=-83.47, y=53.28, z=-56.47], ro['Bat'/22, l='MpServer', x=-94.28, y=12.05, z=-139.31], sc['Squid'/24, l='MpServer', x=-85.05, y=55.89, z=-36.33], ro['Bat'/29, l='MpServer', x=-59.06, y=39.14, z=-148.78], ro['Bat'/28, l='MpServer', x=-75.20, y=34.01, z=-159.13], ro['Bat'/30, l='MpServer', x=-55.34, y=17.00, z=-52.72]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server

-- System Details --
Details:
	Minecraft Version: 1.6.4
	Operating System: Windows Vista (x86) version 6.0
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 40935344 bytes (39 MB) / 156086272 bytes (148 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 9110 (510160 bytes; 0 MB) allocated, 148 (8288 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Launched Version: 1.6.4
	LWJGL: 2.9.0
	OpenGL: GeForce 9400M G/PCI/SSE2 GL version 3.0.0, NVIDIA Corporation
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Pack: Default
	Current Language: English (UK)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 3439 (192584 bytes; 0 MB) allocated, 258 (14448 bytes; 0 MB) used