java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Unknown Source)
	at adv.a(SourceFile:121)
	at adv.a(SourceFile:26)
	at adp.a(SourceFile:349)
	at aer.a(SourceFile:84)
	at agc.a(SourceFile:429)
	at kc.a(SourceFile:156)
	at aez.a(SourceFile:771)
	at kc.c(SourceFile:93)
	at kc.d(SourceFile:104)
	at act.e(SourceFile:311)
	at kd.g(SourceFile:231)
	at kd.b(SourceFile:134)

---- Minecraft Crash Report ----
// You should try our sister game, Minceraft!

Time: 9/6/13 2:49 PM
Description: Exception ticking world

java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Unknown Source)
	at adv.a(SourceFile:121)
	at adv.a(SourceFile:26)
	at adp.a(SourceFile:349)
	at aer.a(SourceFile:84)
	at agc.a(SourceFile:429)
	at kc.a(SourceFile:156)
	at aez.a(SourceFile:771)
	at kc.c(SourceFile:93)
	at kc.d(SourceFile:104)
	at act.e(SourceFile:311)
	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 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:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at java.util.Random.nextInt(Unknown Source)
	at adv.a(SourceFile:121)
	at adv.a(SourceFile:26)
	at adp.a(SourceFile:349)
	at aer.a(SourceFile:84)
	at agc.a(SourceFile:429)
	at kc.a(SourceFile:156)
	at aez.a(SourceFile:771)
	at kc.c(SourceFile:93)
	at kc.d(SourceFile:104)
	at act.e(SourceFile:311)
	at kd.g(SourceFile:231)
	at kd.b(SourceFile:134)

-- Affected level --
Details:
	Level name: ufdtfstsdyts
	All players: 1 total; [kg['rob221'/108, l='ufdtfstsdyts', x=29999999.50, y=69.50, z=29999999.50]]
	Chunk stats: ServerChunkCache: 838 Drop: 0
	Level seed: 48570
	Level generator: ID 00 - default, ver 1. Features enabled: true
	Level generator options: 
	Level spawn location: World: (184,64,236), Chunk: (at 8,4,12 in 11,14; contains blocks 176,0,224 to 191,255,239), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 3399 game time, 3399 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 91952 (now: false), thunder time: 100509 (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 bnn.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:332)
	at hr.run(SourceFile:575)

-- System Details --
Details:
	Minecraft Version: 13w36b
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 161721848 bytes (154 MB) / 402718720 bytes (384 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	AABB Pool Size: 3438 (192528 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 1198 (67088 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Player Count: 1 / 8; [kg['rob221'/108, l='ufdtfstsdyts', x=29999999.50, y=69.50, z=29999999.50]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.