java.lang.IllegalStateException: Failed to add player. mp['kenscy'/0, l='Snapshot 13w', x=778,08, y=59,09, z=1141,91] already is in chunk 40, 63
	at mk.a(SourceFile:37)
	at mj.d(SourceFile:346)
	at lg.d(SourceFile:215)
	at na.a(SourceFile:280)
	at iu.a(SourceFile:137)
	at iv.a(SourceFile:63)
	at ef.a(SourceFile:164)

---- Minecraft Crash Report ----
// On the bright side, I bought you a teddy bear!

Time: 05/12/13 15.47
Description: Ticking memory connection

java.lang.IllegalStateException: Failed to add player. mp['kenscy'/0, l='Snapshot 13w', x=778,08, y=59,09, z=1141,91] already is in chunk 40, 63
	at mk.a(SourceFile:37)
	at mj.d(SourceFile:346)
	at lg.d(SourceFile:215)
	at na.a(SourceFile:280)
	at iu.a(SourceFile:137)
	at iv.a(SourceFile:63)
	at ef.a(SourceFile:164)
	at mv.c(SourceFile:134)
	at net.minecraft.server.MinecraftServer.u(SourceFile:528)
	at net.minecraft.server.MinecraftServer.t(SourceFile:440)
	at bti.t(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:357)
	at lb.run(SourceFile:616)


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

-- Head --
Stacktrace:
	at mk.a(SourceFile:37)
	at mj.d(SourceFile:346)
	at lg.d(SourceFile:215)
	at na.a(SourceFile:280)
	at iu.a(SourceFile:137)
	at iv.a(SourceFile:63)
	at ef.a(SourceFile:164)

-- Ticking connection --
Details:
	Connection: ef@1f3c656
Stacktrace:
	at mv.c(SourceFile:134)
	at net.minecraft.server.MinecraftServer.u(SourceFile:528)
	at net.minecraft.server.MinecraftServer.t(SourceFile:440)
	at bti.t(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:357)
	at lb.run(SourceFile:616)

-- System Details --
Details:
	Minecraft Version: 13w49a
	Operating System: Windows 8 (x86) version 6.2
	Java Version: 1.7.0_40, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 101010344 bytes (96 MB) / 276279296 bytes (263 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	AABB Pool Size: 62 (3472 bytes; 0 MB) allocated, 23 (1288 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 4 (224 bytes; 0 MB) allocated, 1 (56 bytes; 0 MB) used
	Player Count: 1 / 8; [mp['kenscy'/0, l='Snapshot 13w', x=778,08, y=59,09, z=1141,91]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.