Hopper: java.lang.ArrayIndexOutOfBoundsException: -5

java.lang.ArrayIndexOutOfBoundsException: -5
	at b.a(SourceFile:248)
	at act.a(SourceFile:2591)
	at net.minecraft.server.MinecraftServer.t(SourceFile:466)
	at net.minecraft.server.MinecraftServer.s(SourceFile:398)
	at bnn.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:332)
	at hr.run(SourceFile:575)

---- Minecraft Crash Report ----
// Why is it breaking :(

Time: 13-09-06 21:19
Description: Exception in server tick loop

java.lang.ArrayIndexOutOfBoundsException: -5
	at b.a(SourceFile:248)
	at act.a(SourceFile:2591)
	at net.minecraft.server.MinecraftServer.t(SourceFile:466)
	at net.minecraft.server.MinecraftServer.s(SourceFile:398)
	at bnn.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:332)
	at hr.run(SourceFile:575)


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: 13w36b
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_11, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 129129176 bytes (123 MB) / 954466304 bytes (910 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	AABB Pool Size: 1828 (102368 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 939 (52584 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Player Count: 1 / 8; [kg['The__Ender_Demon'/1756652, l='New World', x=2703,89, y=56,00, z=-1928,42]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.