Hopper: java.lang.IllegalArgumentException: Invalid operation

java.lang.IllegalArgumentException: Invalid operation
	at org.apache.commons.lang3.Validate.inclusiveBetween(Validate.java:921)
	at rv.<init>(SourceFile:30)
	at wv.a(SourceFile:94)
	at abp.D(SourceFile:594)
	at rh.h(SourceFile:1199)
	at xl.h(SourceFile:240)

---- Minecraft Crash Report ----
// I feel sad now :(

Time: 10/25/13 11:56 PM
Description: Ticking player

java.lang.IllegalArgumentException: Invalid operation
	at org.apache.commons.lang3.Validate.inclusiveBetween(Validate.java:921)
	at rv.<init>(SourceFile:30)
	at wv.a(SourceFile:94)
	at abp.D(SourceFile:594)
	at rh.h(SourceFile:1199)
	at xl.h(SourceFile:240)
	at mm.i(SourceFile:207)
	at mx.a(SourceFile:209)
	at ir.a(SourceFile:137)
	at it.a(SourceFile:20)
	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 org.apache.commons.lang3.Validate.inclusiveBetween(Validate.java:921)
	at rv.<init>(SourceFile:30)
	at wv.a(SourceFile:94)
	at abp.D(SourceFile:594)
	at rh.h(SourceFile:1199)
	at xl.h(SourceFile:240)

-- Player being ticked --
Details:
	Entity Type: null (mm)
	Entity ID: 149
	Entity Name: amenon
	Entity's Exact location: -805.93, 97.53, -1532.53
	Entity's Block location: World: (-806,97,-1533), Chunk: (at 10,6,3 in -51,-96; contains blocks -816,0,-1536 to -801,255,-1521), Region: (-2,-3; contains chunks -64,-96 to -33,-65, blocks -1024,0,-1536 to -513,255,-1025)
	Entity's Momentum: 0.00, 0.00, 0.00
Stacktrace:
	at mm.i(SourceFile:207)
	at mx.a(SourceFile:209)
	at ir.a(SourceFile:137)
	at it.a(SourceFile:20)
	at ef.a(SourceFile:164)

-- Ticking connection --
Details:
	Connection: ef@1d1e0dd3
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: Mac OS X (x86_64) version 10.6.8
	Java Version: 1.6.0_29, Apple Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
	Memory: 87510952 bytes (83 MB) / 310829056 bytes (296 MB) up to 1065025536 bytes (1015 MB)
	JVM Flags: 1 total; -Xmx1G
	AABB Pool Size: 2252 (126112 bytes; 0 MB) allocated, 2063 (115528 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 313 (17528 bytes; 0 MB) allocated, 311 (17416 bytes; 0 MB) used
	Player Count: 1 / 8; [mm['amenon'/149, l='R', x=-805.93, y=97.53, z=-1532.53]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.