Hopper: java.lang.ArrayIndexOutOfBoundsException: -1

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-34761/

Crash:

java.lang.ArrayIndexOutOfBoundsException: -1
	at acu.a(SourceFile:81)
	at acs.<init>(SourceFile:29)
	at acr.a(SourceFile:59)
	at acr.b(SourceFile:68)
	at acu.a(SourceFile:61)
	at adq.a(SourceFile:865)
	at abv.a(SourceFile:92)
	at ack.a(SourceFile:163)
	at aok.c(SourceFile:73)
	at bfo.p(SourceFile:3620)
	at bfo.b(SourceFile:121)
	at bex.a(SourceFile:160)
	at bfi.a(SourceFile:1131)
	at bfb.a(SourceFile:814)

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

---- Minecraft Crash Report ----
// Uh... Did I do that?

Time: 8/11/13 1:07 PM
Description: Unexpected error

java.lang.ArrayIndexOutOfBoundsException: -1
	at acu.a(SourceFile:81)
	at acs.<init>(SourceFile:29)
	at acr.a(SourceFile:59)
	at acr.b(SourceFile:68)
	at acu.a(SourceFile:61)
	at adq.a(SourceFile:865)
	at abv.a(SourceFile:92)
	at ack.a(SourceFile:163)
	at aok.c(SourceFile:73)
	at bfo.p(SourceFile:3620)
	at bfo.b(SourceFile:121)
	at bex.a(SourceFile:160)
	at bfi.a(SourceFile:1131)
	at bfb.a(SourceFile:814)
	at bfb.b(SourceFile:693)
	at ats.S(SourceFile:686)
	at ats.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 acu.a(SourceFile:81)
	at acs.<init>(SourceFile:29)
	at acr.a(SourceFile:59)
	at acr.b(SourceFile:68)
	at acu.a(SourceFile:61)
	at adq.a(SourceFile:865)
	at abv.a(SourceFile:92)
	at ack.a(SourceFile:163)
	at aok.c(SourceFile:73)
	at bfo.p(SourceFile:3620)
	at bfo.b(SourceFile:121)
	at bex.a(SourceFile:160)
	at bfi.a(SourceFile:1131)
	at bfb.a(SourceFile:814)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bdf['captinzombie3'/139, l='MpServer', x=22.76, y=66.12, z=66.90]]
	Chunk stats: MultiplayerChunkCache: 25
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (12,65,67), Chunk: (at 12,4,3 in 0,4; contains blocks 0,0,64 to 15,255,79), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 4900 game time, 4900 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: 5 total; [sr['item.tile.chest'/71, l='MpServer', x=4.00, y=64.13, z=62.72], bdf['captinzombie3'/139, l='MpServer', x=22.76, y=66.12, z=66.90], sr['item.tile.chest'/72, l='MpServer', x=7.34, y=64.13, z=58.88], sr['item.tile.chest'/73, l='MpServer', x=5.84, y=64.13, z=63.75], sr['item.tile.grass'/74, l='MpServer', x=13.91, y=64.13, z=78.91]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bda.a(SourceFile:284)
	at ats.b(SourceFile:1761)
	at ats.d(SourceFile:633)
	at net.minecraft.client.main.Main.main(SourceFile:101)

-- System Details --
Details:
	Minecraft Version: 1.6.2
	Operating System: Windows 8 (x86) version 6.2
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 65782520 bytes (62 MB) / 180158464 bytes (171 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 4627 (259112 bytes; 0 MB) allocated, 4627 (259112 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 5, allocated: 3, tallocated: 63
	Launched Version: 1.6.2
	LWJGL: 2.9.0
	OpenGL: Intel(R) HD Graphics 3000 GL version 3.1.0 - Build 9.17.10.2828, Intel
	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: 28 (1568 bytes; 0 MB) allocated, 28 (1568 bytes; 0 MB) used

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-34761/2191561/