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-467871/

Crash:

java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Unknown Source)
	at agm.a(SourceFile:122)
	at agm.a(SourceFile:27)
	at agg.a(SourceFile:362)
	at apl.a(SourceFile:432)
	at mi.a(SourceFile:160)
	at aoj.a(SourceFile:775)
	at mi.c(SourceFile:95)
	at mh.<init>(SourceFile:31)
	at mg.a(SourceFile:212)
	at mg.d(SourceFile:346)
	at ld.d(SourceFile:215)
	at mx.a(SourceFile:280)
	at ir.a(SourceFile:137)
	at is.a(SourceFile:63)
	at ef.a(SourceFile:164)

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

---- Minecraft Crash Report ----
// Oh - I know what I did wrong!

Time: 25/10/13 19:25
Description: Ticking memory connection

java.lang.IllegalArgumentException: n must be positive
	at java.util.Random.nextInt(Unknown Source)
	at agm.a(SourceFile:122)
	at agm.a(SourceFile:27)
	at agg.a(SourceFile:362)
	at apl.a(SourceFile:432)
	at mi.a(SourceFile:160)
	at aoj.a(SourceFile:775)
	at mi.c(SourceFile:95)
	at mh.<init>(SourceFile:31)
	at mg.a(SourceFile:212)
	at mg.d(SourceFile:346)
	at ld.d(SourceFile:215)
	at mx.a(SourceFile:280)
	at ir.a(SourceFile:137)
	at is.a(SourceFile:63)
	at ef.a(SourceFile:164)
	at ms.c(SourceFile:134)
	at net.minecraft.server.MinecraftServer.u(SourceFile:529)
	at net.minecraft.server.MinecraftServer.t(SourceFile:441)
	at bsk.t(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:358)
	at ky.run(SourceFile:617)


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 agm.a(SourceFile:122)
	at agm.a(SourceFile:27)
	at agg.a(SourceFile:362)
	at apl.a(SourceFile:432)
	at mi.a(SourceFile:160)
	at aoj.a(SourceFile:775)
	at mi.c(SourceFile:95)
	at mh.<init>(SourceFile:31)
	at mg.a(SourceFile:212)
	at mg.d(SourceFile:346)
	at ld.d(SourceFile:215)
	at mx.a(SourceFile:280)
	at ir.a(SourceFile:137)
	at is.a(SourceFile:63)
	at ef.a(SourceFile:164)

-- Ticking connection --
Details:
	Connection: ef@621bae1e
Stacktrace:
	at ms.c(SourceFile:134)
	at net.minecraft.server.MinecraftServer.u(SourceFile:529)
	at net.minecraft.server.MinecraftServer.t(SourceFile:441)
	at bsk.t(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:358)
	at ky.run(SourceFile:617)

-- System Details --
Details:
	Minecraft Version: 1.7.2
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_21, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 236941784 bytes (225 MB) / 816447488 bytes (778 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	AABB Pool Size: 7343 (411208 bytes; 0 MB) allocated, 6619 (370664 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 2549 (142744 bytes; 0 MB) allocated, 1235 (69160 bytes; 0 MB) used
	Player Count: 1 / 8; [mm['NickBambridge'/1370268, l='Hand Crafted Version 2', x=501.94, y=133.49, z=-1025.15]]
	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-467871/21447890/