---- Minecraft Crash Report ----
// Would you like a cupcake?

Time: 18.01.13 15:11
Description: Adding entity to track

java.lang.IllegalStateException: Entity is already tracked!
	at ik.a(SourceFile:76)
	at ik.a(SourceFile:61)
	at im.a(SourceFile:24)
	at yv.a(SourceFile:843)
	at iq.a(SourceFile:610)
	at yv.d(SourceFile:835)
	at alm.k(SourceFile:55)
	at alm.a(SourceFile:35)
	at iq.a(SourceFile:414)
	at iq.b(SourceFile:131)
	at net.minecraft.server.MinecraftServer.r(SourceFile:452)
	at net.minecraft.server.MinecraftServer.q(SourceFile:395)
	at bhc.q(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:329)
	at gi.run(SourceFile:565)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Entity To Track --
Details:
	Tracking range: 144 blocks
	Update interval: Once per 20 ticks
	Entity Type: FallingSand (qh)
	Entity ID: 6669
	Entity Name: Falling Block
	Entity's Exact location: -149,50, 56,50, 210,50
	Entity's Block location: World: (-150,56,210), Chunk: (at 10,3,2 in -10,13; contains blocks -160,0,208 to -145,255,223), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
	Entity's Momentum: 0,00, 0,00, 0,00
	Immitating block ID: 13
	Immitating block data: 0
Stacktrace:
	at ik.a(SourceFile:76)
	at ik.a(SourceFile:61)
	at im.a(SourceFile:24)
	at yv.a(SourceFile:843)
	at iq.a(SourceFile:610)
	at yv.d(SourceFile:835)
	at alm.k(SourceFile:55)
	at alm.a(SourceFile:35)

-- Block being ticked --
Details:
	Block type: ID #13 (tile.gravel // alj)
	Block data value: 0 / 0x0 / 0b0000
	Block location: World: (-150,56,210), Chunk: (at 10,3,2 in -10,13; contains blocks -160,0,208 to -145,255,223), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Stacktrace:
	at iq.a(SourceFile:414)
	at iq.b(SourceFile:131)

-- Affected level --
Details:
	Level name: New World
	All players: 1 total; [it['sashok724'/179, l='New World', x=-138,96, y=63,00, z=240,93]]
	Chunk stats: ServerChunkCache: 562 Drop: 0
	Level seed: 6336112769274612588
	Level generator: ID 00 - default, ver 1. Features enabled: true
	Level generator options: 
	Level spawn location: World: (-160,64,292), Chunk: (at 0,4,4 in -10,18; contains blocks -160,0,288 to -145,255,303), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
	Level time: 302 game time, 302 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 99489 (now: false), thunder time: 120451 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: true
Stacktrace:
	at net.minecraft.server.MinecraftServer.r(SourceFile:452)
	at net.minecraft.server.MinecraftServer.q(SourceFile:395)
	at bhc.q(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:329)
	at gi.run(SourceFile:565)

-- System Details --
Details:
	Minecraft Version: 13w03a
	Operating System: Windows 8 (amd64) version 6.2
	Java Version: 1.7.0_10, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 391469648 bytes (373 MB) / 598671360 bytes (570 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -Xms512m -Xmx1024m
	AABB Pool Size: 7572 (424032 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 3, tallocated: 63
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 1680 (94080 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Player Count: 1 / 8; [it['sashok724'/179, l='New World', x=-138,96, y=63,00, z=240,93]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.