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:458)
	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 ----
// I feel sad now :(

Time: 9/7/13 5:56 PM
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:458)
	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: Mac OS X (x86_64) version 10.6.8
	Java Version: 1.6.0_51, Apple Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
	Memory: 8071288 bytes (7 MB) / 1069416448 bytes (1019 MB) up to 1069416448 bytes (1019 MB)
	JVM Flags: 1 total; -Xmx1G
	AABB Pool Size: 3628 (203168 bytes; 0 MB) allocated, 4 (224 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 6818 (381808 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Player Count: 1 / 8; [kg['hayleyw747'/4519, l='New World', x=-265.70, y=-280.69, z=-102.30]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.