Hopper: java.lang.ArrayIndexOutOfBoundsException: -1

java.lang.ArrayIndexOutOfBoundsException: -1
	at acv.b(SourceFile:114)
	at act.<init>(SourceFile:28)
	at acs.a(SourceFile:59)
	at acs.b(SourceFile:68)
	at acv.a(SourceFile:61)
	at adr.a(SourceFile:865)
	at abw.a(SourceFile:92)
	at abw.a(SourceFile:1030)
	at bfe.i(SourceFile:1184)
	at bfe.a(SourceFile:784)

---- Minecraft Crash Report ----
// There are four lights!

Time: 19/09/13 12:47 PM
Description: Unexpected error

java.lang.ArrayIndexOutOfBoundsException: -1
	at acv.b(SourceFile:114)
	at act.<init>(SourceFile:28)
	at acs.a(SourceFile:59)
	at acs.b(SourceFile:68)
	at acv.a(SourceFile:61)
	at adr.a(SourceFile:865)
	at abw.a(SourceFile:92)
	at abw.a(SourceFile:1030)
	at bfe.i(SourceFile:1184)
	at bfe.a(SourceFile:784)
	at bfe.b(SourceFile:695)
	at atv.S(SourceFile:686)
	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 acv.b(SourceFile:114)
	at act.<init>(SourceFile:28)
	at acs.a(SourceFile:59)
	at acs.b(SourceFile:68)
	at acv.a(SourceFile:61)
	at adr.a(SourceFile:865)
	at abw.a(SourceFile:92)
	at abw.a(SourceFile:1030)
	at bfe.i(SourceFile:1184)
	at bfe.a(SourceFile:784)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bdi['PolarPancakes'/165, l='MpServer', x=8.50, y=66.62, z=8.50]]
	Chunk stats: MultiplayerChunkCache: 0
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (168,64,252), Chunk: (at 8,4,12 in 10,15; contains blocks 160,0,240 to 175,255,255), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 1102301 game time, 1510512 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: survival (ID 0). Hardcore: false. Cheats: false
	Forced entities: 1 total; [bdi['PolarPancakes'/165, l='MpServer', x=8.50, y=66.62, z=8.50]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bdd.a(SourceFile:284)
	at atv.b(SourceFile:1761)
	at atv.d(SourceFile:633)
	at net.minecraft.client.main.Main.main(SourceFile:101)

-- System Details --
Details:
	Minecraft Version: 1.6.4
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_17, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 330569720 bytes (315 MB) / 443809792 bytes (423 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	AABB Pool Size: 10819 (605864 bytes; 0 MB) allocated, 10819 (605864 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 3, tallocated: 63
	Launched Version: 1.6.4
	LWJGL: 2.9.0
	OpenGL: AMD Radeon HD 6520G GL version 4.2.12217 Compatibility Profile Context 12.104.0.0, ATI Technologies Inc.
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Pack: Default
	Current Language: English (US)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 12 (672 bytes; 0 MB) allocated, 12 (672 bytes; 0 MB) used