Hopper: java.lang.IllegalArgumentException: Invalid operation

java.lang.IllegalArgumentException: Invalid operation
	at org.apache.commons.lang3.Validate.inclusiveBetween(Validate.java:921)
	at pi.<init>(SourceFile:32)
	at ug.a(SourceFile:92)
	at yx.D(SourceFile:581)
	at ou.o_(SourceFile:1188)
	at uw.o_(SourceFile:204)

---- Minecraft Crash Report ----
// Shall we play a game?

Time: 08.09.13 09:59
Description: Ticking player

java.lang.IllegalArgumentException: Invalid operation
	at org.apache.commons.lang3.Validate.inclusiveBetween(Validate.java:921)
	at pi.<init>(SourceFile:32)
	at ug.a(SourceFile:92)
	at yx.D(SourceFile:581)
	at ou.o_(SourceFile:1188)
	at uw.o_(SourceFile:204)
	at kg.h(SourceFile:192)
	at kl.a(SourceFile:195)
	at fd.a(SourceFile:136)
	at cv.b(SourceFile:64)
	at kl.e(SourceFile:63)
	at ko.b(SourceFile:37)
	at bnq.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.t(SourceFile:481)
	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 org.apache.commons.lang3.Validate.inclusiveBetween(Validate.java:921)
	at pi.<init>(SourceFile:32)
	at ug.a(SourceFile:92)
	at yx.D(SourceFile:581)
	at ou.o_(SourceFile:1188)
	at uw.o_(SourceFile:204)

-- Player being ticked --
Details:
	Entity Type: null (kg)
	Entity ID: 137
	Entity Name: nicosdisaster
	Entity's Exact location: 287,05, 56,00, -1270,11
	Entity's Block location: World: (287,56,-1271), Chunk: (at 15,3,9 in 17,-80; contains blocks 272,0,-1280 to 287,255,-1265), Region: (0,-3; contains chunks 0,-96 to 31,-65, blocks 0,0,-1536 to 511,255,-1025)
	Entity's Momentum: 0,00, -0,08, 0,00
Stacktrace:
	at kg.h(SourceFile:192)
	at kl.a(SourceFile:195)
	at fd.a(SourceFile:136)
	at cv.b(SourceFile:64)
	at kl.e(SourceFile:63)

-- Ticking connection --
Details:
	Connection: kl@15f0269
Stacktrace:
	at ko.b(SourceFile:37)
	at bnq.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.t(SourceFile:481)
	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 Vista (x86) version 6.0
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 123803040 bytes (118 MB) / 315645952 bytes (301 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 1915 (107240 bytes; 0 MB) allocated, 1915 (107240 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 258 (14448 bytes; 0 MB) allocated, 258 (14448 bytes; 0 MB) used
	Player Count: 1 / 8; [kg['nicosdisaster'/137, l='Redstone Welt', x=287,05, y=56,00, z=-1270,11]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.