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-76131/

Crash:

java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Random.java:250)
	at adu.a(SourceFile:121)
	at adu.a(SourceFile:26)
	at ado.a(SourceFile:350)
	at agb.a(SourceFile:433)
	at kc.a(SourceFile:156)
	at aey.a(SourceFile:774)
	at kc.c(SourceFile:93)
	at kb.<init>(SourceFile:28)
	at ka.a(SourceFile:209)
	at ka.a(SourceFile:246)
	at hx.a(SourceFile:151)
	at hx.c(SourceFile:199)
	at hx.a(SourceFile:95)
	at bnj.b(SourceFile:73)
	at net.minecraft.server.MinecraftServer.t(SourceFile:481)
	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)

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

---- Minecraft Crash Report ----
// I let you down. Sorry :(

Time: 9/5/13 6:10 PM
Description: Exception in server tick loop

java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Random.java:250)
	at adu.a(SourceFile:121)
	at adu.a(SourceFile:26)
	at ado.a(SourceFile:350)
	at agb.a(SourceFile:433)
	at kc.a(SourceFile:156)
	at aey.a(SourceFile:774)
	at kc.c(SourceFile:93)
	at kb.<init>(SourceFile:28)
	at ka.a(SourceFile:209)
	at ka.a(SourceFile:246)
	at hx.a(SourceFile:151)
	at hx.c(SourceFile:199)
	at hx.a(SourceFile:95)
	at bnj.b(SourceFile:73)
	at net.minecraft.server.MinecraftServer.t(SourceFile:481)
	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:
---------------------------------------------------------------------------------------

-- System Details --
Details:
	Minecraft Version: 13w36a
	Operating System: Mac OS X (x86_64) version 10.7.5
	Java Version: 1.6.0_51, Apple Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
	Memory: 3388600 bytes (3 MB) / 96583680 bytes (92 MB) up to 1065025536 bytes (1015 MB)
	JVM Flags: 1 total; -Xmx1G
	AABB Pool Size: 1251 (70056 bytes; 0 MB) allocated, 1251 (70056 bytes; 0 MB) used
	Suspicious classes: [com.ibm.icu.text.ArabicShapingException], [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: 181 (10136 bytes; 0 MB) allocated, 181 (10136 bytes; 0 MB) used
	Player Count: 1 / 8; [kg['amon1234567'/151, l='New World', x=-12098.50, y=150.50, z=29999999.50]]
	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-76131/8196918/