Hopper: java.lang.ArrayIndexOutOfBoundsException: -5

java.lang.ArrayIndexOutOfBoundsException: -5
	at b.a(SourceFile:330)
	at abw.a(SourceFile:2577)
	at net.minecraft.server.MinecraftServer.t(SourceFile:466)
	at net.minecraft.server.MinecraftServer.s(SourceFile:406)
	at bkz.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:340)
	at hi.run(SourceFile:583)

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

Time: 20/09/13 8:15 PM
Description: Exception in server tick loop

java.lang.ArrayIndexOutOfBoundsException: -5
	at b.a(SourceFile:330)
	at abw.a(SourceFile:2577)
	at net.minecraft.server.MinecraftServer.t(SourceFile:466)
	at net.minecraft.server.MinecraftServer.s(SourceFile:406)
	at bkz.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:340)
	at hi.run(SourceFile:583)


A detailed walkthrough of the error, its code path and all known details is as follows:
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-- System Details --
Details:
	Minecraft Version: 1.6.4
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_05, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 109223616 bytes (104 MB) / 785580032 bytes (749 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	AABB Pool Size: 301291 (16872296 bytes; 16 MB) allocated, 0 (0 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 3, tallocated: 63
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 102247 (5725832 bytes; 5 MB) allocated, 0 (0 bytes; 0 MB) used
	Player Count: 1 / 8; [jv['coldtim'/260919, l='New World', x=-812.64, y=33.00, z=908.30]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.