Hopper: java.lang.RuntimeException: Already decorating!!

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-4791/

Crash:

java.lang.RuntimeException: Already decorating!!
	at act.a(SourceFile:21)
	at acp.a(SourceFile:217)
	at aes.a(SourceFile:454)
	at jq.a(SourceFile:168)
	at adq.a(SourceFile:723)
	at jq.c(SourceFile:105)
	at jq.d(SourceFile:116)
	at abv.e(SourceFile:289)

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

---- Minecraft Crash Report ----
// Uh... Did I do that?

Time: 8/2/13 10:54 AM
Description: Exception getting block type in world

java.lang.RuntimeException: Already decorating!!
	at act.a(SourceFile:21)
	at acp.a(SourceFile:217)
	at aes.a(SourceFile:454)
	at jq.a(SourceFile:168)
	at adq.a(SourceFile:723)
	at jq.c(SourceFile:105)
	at jq.d(SourceFile:116)
	at abv.e(SourceFile:289)
	at abv.a(SourceFile:213)
	at abv.g(SourceFile:464)
	at abv.f(SourceFile:445)
	at abv.d(SourceFile:415)
	at abv.f(SourceFile:316)
	at abv.i(SourceFile:378)
	at aop.k(SourceFile:46)
	at aop.a(SourceFile:35)
	at jr.a(SourceFile:404)
	at jr.b(SourceFile:130)
	at net.minecraft.server.MinecraftServer.t(SourceFile:462)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bkw.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at hh.run(SourceFile:582)


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

-- Head --
Stacktrace:
	at act.a(SourceFile:21)
	at acp.a(SourceFile:217)
	at aes.a(SourceFile:454)
	at jq.a(SourceFile:168)
	at adq.a(SourceFile:723)
	at jq.c(SourceFile:105)
	at jq.d(SourceFile:116)
	at abv.e(SourceFile:289)

-- Requested block coordinates --
Details:
	Found chunk: true
	Location: World: (207,54,-100), Chunk: (at 15,3,12 in 12,-7; contains blocks 192,0,-112 to 207,255,-97), Region: (0,-1; contains chunks 0,-32 to 31,-1, blocks 0,0,-512 to 511,255,-1)
Stacktrace:
	at abv.a(SourceFile:213)
	at abv.g(SourceFile:464)
	at abv.f(SourceFile:445)
	at abv.d(SourceFile:415)
	at abv.f(SourceFile:316)
	at abv.i(SourceFile:378)
	at aop.k(SourceFile:46)
	at aop.a(SourceFile:35)

-- Block being ticked --
Details:
	Block type: ID #12 (tile.sand // aop)
	Block data value: 0 / 0x0 / 0b0000
	Block location: World: (208,54,-100), Chunk: (at 0,3,12 in 13,-7; contains blocks 208,0,-112 to 223,255,-97), Region: (0,-1; contains chunks 0,-32 to 31,-1, blocks 0,0,-512 to 511,255,-1)
Stacktrace:
	at jr.a(SourceFile:404)
	at jr.b(SourceFile:130)

-- Affected level --
Details:
	Level name: Brandon's world
	All players: 0 total; []
	Chunk stats: ServerChunkCache: 504 Drop: 0
	Level seed: -4616341889734479565
	Level generator: ID 00 - default, ver 1. Features enabled: true
	Level generator options: 
	Level spawn location: World: (41,64,-118), Chunk: (at 9,4,10 in 2,-8; contains blocks 32,0,-128 to 47,255,-113), Region: (0,-1; contains chunks 0,-32 to 31,-1, blocks 0,0,-512 to 511,255,-1)
	Level time: 314 game time, 314 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 29141 (now: false), thunder time: 81861 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: true
Stacktrace:
	at net.minecraft.server.MinecraftServer.t(SourceFile:462)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bkw.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at hh.run(SourceFile:582)

-- System Details --
Details:
	Minecraft Version: 1.6.2
	Operating System: Windows 8 (x86) version 6.2
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 98447632 bytes (93 MB) / 294170624 bytes (280 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 4969 (278264 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: 7955 (445480 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Player Count: 0 / 8; []
	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-4791/49899/