Hopper: java.lang.NullPointerException: Loading entity NBT

java.lang.NullPointerException: Loading entity NBT
	at re.i(SourceFile:151)
	at rq.b(SourceFile:135)
	at rf.a(SourceFile:112)
	at rf.a(SourceFile:138)

---- Minecraft Crash Report ----
// I let you down. Sorry :(

Time: 15:44 25/10/13
Description: Loading entity NBT

java.lang.NullPointerException: Loading entity NBT
	at re.i(SourceFile:151)
	at rq.b(SourceFile:135)
	at rf.a(SourceFile:112)
	at rf.a(SourceFile:138)
	at qn.f(SourceFile:1089)
	at afc.a(SourceFile:117)
	at afc.h(SourceFile:236)
	at bmh.a(SourceFile:20)
	at bmh.a(SourceFile:15)
	at bmh.a(SourceFile:10)
	at bmc.a(SourceFile:100)
	at bmc.a(SourceFile:92)
	at bls.a(SourceFile:382)
	at bll.a(SourceFile:984)
	at bll.b(SourceFile:813)
	at azd.ad(SourceFile:780)
	at azd.e(SourceFile:704)
	at net.minecraft.client.main.Main.main(SourceFile:103)


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

-- Head --
Stacktrace:
	at re.i(SourceFile:151)
	at rq.b(SourceFile:135)
	at rf.a(SourceFile:112)
	at rf.a(SourceFile:138)

-- Entity being loaded --
Details:
	Entity Type: ItemFrame (rf)
	Entity ID: 67
	Entity Name: entity.ItemFrame.name
	Entity's Exact location: -367.06, 79.50, 1087.50
	Entity's Block location: World: (-368,79,1087), Chunk: (at 0,4,15 in -23,67; contains blocks -368,0,1072 to -353,255,1087), Region: (-1,2; contains chunks -32,64 to -1,95, blocks -512,0,1024 to -1,255,1535)
	Entity's Momentum: 0.00, 0.00, 0.00
Stacktrace:
	at qn.f(SourceFile:1089)
	at afc.a(SourceFile:117)
	at afc.h(SourceFile:236)
	at bmh.a(SourceFile:20)
	at bmh.a(SourceFile:15)
	at bmh.a(SourceFile:10)

-- Block Entity Details --
Details:
	Name: MobSpawner // anv
	Block type: ID #52 (tile.mobSpawner // akm)
	Block data value: 15 / 0xF / 0b1111
	Block location: World: (-366,79,1087), Chunk: (at 2,4,15 in -23,67; contains blocks -368,0,1072 to -353,255,1087), Region: (-1,2; contains chunks -32,64 to -1,95, blocks -512,0,1024 to -1,255,1535)
	Actual block type: ID #52 (tile.mobSpawner // akm)
	Actual block data value: 15 / 0xF / 0b1111
Stacktrace:
	at bmc.a(SourceFile:100)
	at bmc.a(SourceFile:92)
	at bls.a(SourceFile:382)
	at bll.a(SourceFile:984)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bje['oddworld111'/40, l='MpServer', x=-388.09, y=96.94, z=1095.65]]
	Chunk stats: MultiplayerChunkCache: 20, 20
	Level seed: 0
	Level generator: ID 01 - flat, ver 0. Features enabled: false
	Level generator options: 
	Level spawn location: World: (-388,88,1104), Chunk: (at 12,5,0 in -25,69; contains blocks -400,0,1104 to -385,255,1119), Region: (-1,2; contains chunks -32,64 to -1,95, blocks -512,0,1024 to -1,255,1535)
	Level time: 4010928 game time, 16000 day time
	Level dimension: 0
	Level storage version: 0x00000 - Unknown?
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
	Forced entities: 2 total; [rf['entity.ItemFrame.name'/39, l='MpServer', x=-367.06, y=79.50, z=1087.50], bje['oddworld111'/40, l='MpServer', x=-388.09, y=96.94, z=1095.65]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at biz.a(SourceFile:284)
	at azd.b(SourceFile:1951)
	at azd.e(SourceFile:713)
	at net.minecraft.client.main.Main.main(SourceFile:103)

-- System Details --
Details:
	Minecraft Version: 1.7.2
	Operating System: Windows XP (x86) version 5.1
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 60054952 bytes (57 MB) / 136986624 bytes (130 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 9251 (518056 bytes; 0 MB) allocated, 2 (112 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Launched Version: 1.7.2
	LWJGL: 2.9.0
	OpenGL: GeForce 9500 GT/PCI/SSE2 GL version 3.0.0, NVIDIA Corporation
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: []
	Current Language: ????? (IL)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 253 (14168 bytes; 0 MB) allocated, 44 (2464 bytes; 0 MB) used
	Anisotropic Filtering: Off (1)