Hopper: java.lang.IllegalArgumentException: n must be positive

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-12115/

Crash:

java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Unknown Source)
	at aav.a(SourceFile:144)
	at oe.c(SourceFile:800)
	at ue.d(SourceFile:737)
	at oe.a(SourceFile:570)
	at ue.a(SourceFile:694)
	at ju.a(SourceFile:262)
	at nm.z(SourceFile:382)
	at nm.x(SourceFile:358)
	at oe.x(SourceFile:163)
	at nm.l_(SourceFile:278)
	at oe.l_(SourceFile:1149)
	at ue.l_(SourceFile:203)

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

---- Minecraft Crash Report ----
// On the bright side, I bought you a teddy bear!

Time: 03/08/13 12:23
Description: Ticking player

java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Unknown Source)
	at aav.a(SourceFile:144)
	at oe.c(SourceFile:800)
	at ue.d(SourceFile:737)
	at oe.a(SourceFile:570)
	at ue.a(SourceFile:694)
	at ju.a(SourceFile:262)
	at nm.z(SourceFile:382)
	at nm.x(SourceFile:358)
	at oe.x(SourceFile:163)
	at nm.l_(SourceFile:278)
	at oe.l_(SourceFile:1149)
	at ue.l_(SourceFile:203)
	at ju.h(SourceFile:180)
	at jz.a(SourceFile:190)
	at et.a(SourceFile:136)
	at cm.b(SourceFile:64)
	at jz.e(SourceFile:60)
	at kc.b(SourceFile:37)
	at bkz.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.t(SourceFile:488)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bkw.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at hh.run(SourceFile:582)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at java.util.Random.nextInt(Unknown Source)
	at aav.a(SourceFile:144)
	at oe.c(SourceFile:800)
	at ue.d(SourceFile:737)
	at oe.a(SourceFile:570)
	at ue.a(SourceFile:694)
	at ju.a(SourceFile:262)
	at nm.z(SourceFile:382)
	at nm.x(SourceFile:358)
	at oe.x(SourceFile:163)
	at nm.l_(SourceFile:278)
	at oe.l_(SourceFile:1149)
	at ue.l_(SourceFile:203)

-- Player being ticked --
Details:
	Entity Type: null (ju)
	Entity ID: 178
	Entity Name: ReternedHerobrine
	Entity's Exact location: 76.14, 59.00, -35.07
	Entity's Block location: World: (76,59,-36), Chunk: (at 12,3,12 in 4,-3; contains blocks 64,0,-48 to 79,255,-33), Region: (0,-1; contains chunks 0,-32 to 31,-1, blocks 0,0,-512 to 511,255,-1)
	Entity's Momentum: 0.00, -0.08, 0.00
Stacktrace:
	at ju.h(SourceFile:180)
	at jz.a(SourceFile:190)
	at et.a(SourceFile:136)
	at cm.b(SourceFile:64)
	at jz.e(SourceFile:60)

-- Ticking connection --
Details:
	Connection: jz@2d13df
Stacktrace:
	at kc.b(SourceFile:37)
	at bkz.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.t(SourceFile:488)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bkw.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at hh.run(SourceFile:582)

-- System Details --
Details:
	Minecraft Version: 1.6.2
	Operating System: Windows 7 (x86) version 6.1
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 111378664 bytes (106 MB) / 295862272 bytes (282 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 3968 (222208 bytes; 0 MB) allocated, 3428 (191968 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 1, tallocated: 63
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 372 (20832 bytes; 0 MB) allocated, 254 (14224 bytes; 0 MB) used
	Player Count: 1 / 8; [ju['ReternedHerobrine'/178, l='Cool new world', x=76.14, y=59.00, z=-35.07]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-12115/227466/