java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Unknown Source)
	at adu.a(SourceFile:121)
	at adu.a(SourceFile:26)
	at ado.a(SourceFile:350)
	at aem.a(SourceFile:56)
	at agb.a(SourceFile:433)
	at kc.a(SourceFile:156)
	at aey.a(SourceFile:771)
	at kc.c(SourceFile:93)
	at kc.d(SourceFile:104)
	at act.e(SourceFile:297)
	at kd.g(SourceFile:231)
	at kd.b(SourceFile:134)

---- Minecraft Crash Report ----
// Everything's going to plan. No, really, that was supposed to happen.

Time: 05/09/13 13:00
Description: Exception ticking world

java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Unknown Source)
	at adu.a(SourceFile:121)
	at adu.a(SourceFile:26)
	at ado.a(SourceFile:350)
	at aem.a(SourceFile:56)
	at agb.a(SourceFile:433)
	at kc.a(SourceFile:156)
	at aey.a(SourceFile:771)
	at kc.c(SourceFile:93)
	at kc.d(SourceFile:104)
	at act.e(SourceFile:297)
	at kd.g(SourceFile:231)
	at kd.b(SourceFile:134)
	at net.minecraft.server.MinecraftServer.t(SourceFile:455)
	at net.minecraft.server.MinecraftServer.s(SourceFile:398)
	at bng.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:332)
	at hs.run(SourceFile:575)


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 adu.a(SourceFile:121)
	at adu.a(SourceFile:26)
	at ado.a(SourceFile:350)
	at aem.a(SourceFile:56)
	at agb.a(SourceFile:433)
	at kc.a(SourceFile:156)
	at aey.a(SourceFile:771)
	at kc.c(SourceFile:93)
	at kc.d(SourceFile:104)
	at act.e(SourceFile:297)
	at kd.g(SourceFile:231)
	at kd.b(SourceFile:134)

-- Affected level --
Details:
	Level name: New World
	All players: 1 total; [kg['legorei1'/8704, l='New World', x=29999999,50, y=70,50, z=29999999,50]]
	Chunk stats: ServerChunkCache: 813 Drop: 0
	Level seed: 6746317529941435002
	Level generator: ID 00 - default, ver 1. Features enabled: true
	Level generator options: 
	Level spawn location: World: (160,64,256), Chunk: (at 0,4,0 in 10,16; contains blocks 160,0,256 to 175,255,271), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 4357 game time, 4357 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 29721 (now: false), thunder time: 102204 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: true
Stacktrace:
	at net.minecraft.server.MinecraftServer.t(SourceFile:455)
	at net.minecraft.server.MinecraftServer.s(SourceFile:398)
	at bng.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:332)
	at hs.run(SourceFile:575)

-- System Details --
Details:
	Minecraft Version: 13w36a
	Operating System: Windows XP (x86) version 5.1
	Java Version: 1.7.0_17, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 58313224 bytes (55 MB) / 312954880 bytes (298 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 3 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M -Xmx512M
	AABB Pool Size: 5123 (286888 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Suspicious classes: [com.ibm.icu.impl.UBiDiProps, Authenticate, ICUData, ...], [com.ibm.icu.lang.ECharacterCategory, ECharacterDirection, UCharacter], [com.ibm.icu.text.ArabicShapingException, Bidi, ImpTabPair, ...], [com.ibm.icu.util.ValueIterator, RangeValueIterator], [gnu.trove.TIntCollection], [gnu.trove.impl.HashFunctions, PrimeFinder], [gnu.trove.impl.hash.THash, TPrimitiveHash, TIntIntHash], [gnu.trove.iterator.TIterator, TAdvancingIterator, TIntIntIterator], [gnu.trove.map.TIntIntMap], [gnu.trove.map.hash.TIntIntHashMap], [gnu.trove.procedure.TIntIntProcedure], [gnu.trove.set.TIntSet]
	IntCache: cache: 1, tcache: 1, allocated: 12, tallocated: 94
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 1351 (75656 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Player Count: 1 / 8; [kg['legorei1'/8704, l='New World', x=29999999,50, y=70,50, z=29999999,50]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.