dont know i think it was a spawner on super hstile inferno mines

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

Time: 5/29/13 11:52 PM
Description: Loading entity NBT

java.lang.NullPointerException
	at np.a(SourceFile:357)
	at nq.a(SourceFile:251)
	at sz.a(SourceFile:297)
	at mx.f(SourceFile:1061)
	at aas.a(SourceFile:116)
	at aas.h(SourceFile:234)
	at bhe.a(SourceFile:22)
	at bhe.a(SourceFile:17)
	at bhe.a(SourceFile:12)
	at bhj.a(SourceFile:106)
	at bhj.a(SourceFile:98)
	at bdt.a(SourceFile:317)
	at bdm.a(SourceFile:836)
	at bdm.b(SourceFile:684)
	at asx.R(SourceFile:674)
	at asx.d(SourceFile:607)
	at net.minecraft.client.main.Main.main(SourceFile:78)


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

-- Head --
Stacktrace:
	at np.a(SourceFile:357)
	at nq.a(SourceFile:251)
	at sz.a(SourceFile:297)

-- Entity being loaded --
Details:
	Entity Type: Skeleton (sz)
	Entity ID: 226
	Entity Name: Skeleton
	Entity's Exact location: 0.00, 0.00, 0.00
	Entity's Block location: World: (0,0,0), Chunk: (at 0,0,0 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Entity's Momentum: 0.00, 0.00, 0.00
Stacktrace:
	at mx.f(SourceFile:1061)
	at aas.a(SourceFile:116)
	at aas.h(SourceFile:234)
	at bhe.a(SourceFile:22)
	at bhe.a(SourceFile:17)
	at bhe.a(SourceFile:12)

-- Tile Entity Details --
Details:
	Name: MobSpawner // arm
	Block type: ID #52 (tile.mobSpawner // aol)
	Block data value: 0 / 0x0 / 0b0000
	Block location: World: (-45,52,89), Chunk: (at 3,3,9 in -3,5; contains blocks -48,0,80 to -33,255,95), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
	Actual block type: ID #52 (tile.mobSpawner // aol)
	Actual block data value: 0 / 0x0 / 0b0000
Stacktrace:
	at bhj.a(SourceFile:106)
	at bhj.a(SourceFile:98)
	at bdt.a(SourceFile:317)
	at bdm.a(SourceFile:836)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bbq['douglasdylan50'/12, l='MpServer', x=-77.59, y=88.62, z=75.96]]
	Chunk stats: MultiplayerChunkCache: 441
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (27,135,703), Chunk: (at 11,8,15 in 1,43; contains blocks 16,0,688 to 31,255,703), Region: (0,1; contains chunks 0,32 to 31,63, blocks 0,0,512 to 511,255,1023)
	Level time: 1820538 game time, 616372 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: survival (ID 0). Hardcore: false. Cheats: false
	Forced entities: 31 total; [bbq['douglasdylan50'/12, l='MpServer', x=-77.59, y=88.62, z=75.96], qw['Bat'/14, l='MpServer', x=-151.38, y=39.95, z=101.88], qw['Bat'/134, l='MpServer', x=-6.46, y=52.54, z=149.86], sc['entity.MinecartChest.name'/15, l='MpServer', x=-112.50, y=87.50, z=55.47], sa['item.tile.stoneSlab.sand'/17, l='MpServer', x=-107.88, y=84.13, z=39.13], sg['entity.MinecartRideable.name'/16, l='MpServer', x=-112.22, y=87.50, z=60.50], sg['entity.MinecartRideable.name'/19, l='MpServer', x=-108.75, y=87.50, z=60.50], sg['entity.MinecartRideable.name'/18, l='MpServer', x=-107.50, y=87.50, z=60.50], qw['Bat'/21, l='MpServer', x=-88.81, y=50.42, z=111.59], sg['entity.MinecartRideable.name'/20, l='MpServer', x=-110.47, y=87.50, z=60.50], qw['Bat'/23, l='MpServer', x=-114.34, y=53.92, z=115.09], qw['Bat'/22, l='MpServer', x=-92.09, y=52.98, z=102.53], sa['item.item.bow'/25, l='MpServer', x=-88.19, y=87.13, z=37.69], qw['Bat'/24, l='MpServer', x=-89.78, y=49.76, z=123.34], qw['Bat'/27, l='MpServer', x=-91.47, y=22.67, z=150.25], qw['Bat'/26, l='MpServer', x=-85.16, y=39.48, z=121.81], qw['Bat'/29, l='MpServer', x=-73.03, y=59.45, z=119.53], qw['Bat'/209, l='MpServer', x=-1.37, y=62.59, z=23.69], qw['Bat'/28, l='MpServer', x=-71.66, y=57.07, z=106.13], qw['Bat'/210, l='MpServer', x=2.17, y=61.52, z=12.73], qw['Bat'/211, l='MpServer', x=1.44, y=64.06, z=4.79], qw['Bat'/35, l='MpServer', x=-24.34, y=46.07, z=118.81], qw['Bat'/32, l='MpServer', x=-51.28, y=34.04, z=120.00], sg['entity.MinecartRideable.name'/38, l='MpServer', x=-12.50, y=62.50, z=52.41], sj['entity.MinecartTNT.name'/39, l='MpServer', x=-11.53, y=62.50, z=51.50], sg['entity.MinecartRideable.name'/36, l='MpServer', x=-11.41, y=62.50, z=54.50], sg['entity.MinecartRideable.name'/37, l='MpServer', x=-8.50, y=62.50, z=54.50], sg['entity.MinecartRideable.name'/42, l='MpServer', x=-1.97, y=52.50, z=150.50], sj['entity.MinecartTNT.name'/40, l='MpServer', x=-10.22, y=62.50, z=54.50], sc['entity.MinecartChest.name'/41, l='MpServer', x=-3.53, y=52.50, z=150.50], sc['entity.MinecartChest.name'/47, l='MpServer', x=2.94, y=52.50, z=150.50]]
	Retry entities: 0 total; []
Stacktrace:
	at bbn.a(SourceFile:282)
	at asx.b(SourceFile:1793)
	at asx.d(SourceFile:616)
	at net.minecraft.client.main.Main.main(SourceFile:78)

-- System Details --
Details:
	Minecraft Version: 13w21b
	Operating System: Windows XP (x86) version 5.1
	Java Version: 1.7.0_21, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
	Memory: 250400760 bytes (238 MB) / 569688064 bytes (543 MB) up to 1037959168 bytes (989 MB)
	JVM Flags: 1 total; -Xmx1G
	AABB Pool Size: 1209 (67704 bytes; 0 MB) allocated, 159 (8904 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 9, tcache: 0, allocated: 3, tallocated: 63
	LWJGL: 2.9.0
	OpenGL: Intel 865G GL version 1.4.0 - Build 4.14.10.3762, Intel
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Texture Pack: Default
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 294

What I expected to happen was...:
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What actually happened was...:
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Steps to Reproduce:
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