Hopper: java.lang.NullPointerException at nf.a(SourceFile:89)

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-21981/

Crash:

java.lang.NullPointerException
	at nf.a(SourceFile:89)
	at ob.aF(SourceFile:371)
	at ob.x(SourceFile:214)
	at nj.l_(SourceFile:272)
	at ob.l_(SourceFile:1138)
	at tz.l_(SourceFile:203)

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

---- Minecraft Crash Report ----
// Everything's going to plan. No, really, that was supposed to happen.

Time: 18-08-13 07:57 PM
Description: Ticking player

java.lang.NullPointerException
	at nf.a(SourceFile:89)
	at ob.aF(SourceFile:371)
	at ob.x(SourceFile:214)
	at nj.l_(SourceFile:272)
	at ob.l_(SourceFile:1138)
	at tz.l_(SourceFile:203)
	at jr.h(SourceFile:180)
	at jw.a(SourceFile:205)
	at es.a(SourceFile:136)
	at cl.b(SourceFile:64)
	at jw.d(SourceFile:59)
	at jz.b(SourceFile:37)
	at bkp.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.t(SourceFile:488)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bkm.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at he.run(SourceFile:582)


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

-- Head --
Stacktrace:
	at nf.a(SourceFile:89)
	at ob.aF(SourceFile:371)
	at ob.x(SourceFile:214)
	at nj.l_(SourceFile:272)
	at ob.l_(SourceFile:1138)
	at tz.l_(SourceFile:203)

-- Player being ticked --
Details:
	Entity Type: null (jr)
	Entity ID: 57807
	Entity Name: davidguetalfa
	Entity's Exact location: -55,28, 71,00, 173,51
	Entity's Block location: World: (-56,71,173), Chunk: (at 8,4,13 in -4,10; contains blocks -64,0,160 to -49,255,175), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
	Entity's Momentum: 0,00, -0,08, 0,00
Stacktrace:
	at jr.h(SourceFile:180)
	at jw.a(SourceFile:205)
	at es.a(SourceFile:136)
	at cl.b(SourceFile:64)
	at jw.d(SourceFile:59)

-- Ticking connection --
Details:
	Connection: jw@1c532e5
Stacktrace:
	at jz.b(SourceFile:37)
	at bkp.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.t(SourceFile:488)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bkm.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at he.run(SourceFile:582)

-- System Details --
Details:
	Minecraft Version: 1.6
	Operating System: Windows 7 (x86) version 6.1
	Java Version: 1.7.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 379957776 bytes (362 MB) / 518979584 bytes (494 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 4325 (242200 bytes; 0 MB) allocated, 4017 (224952 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: 1402 (78512 bytes; 0 MB) allocated, 1292 (72352 bytes; 0 MB) used
	Player Count: 1 / 8; [jr['davidguetalfa'/57807, l='snapshot', x=-55,28, y=71,00, z=173,51]]
	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-21981/3992577/