Game Crash when traveling through end portal after updating to 1.4.2 after killing ender dragon in previous ver of game

Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

As far as I know it is still a problem, cuz my world still crashes when I load it.

Note:

Description: Exception in server tick loop
java.lang.IllegalStateException: Entity is already tracked!
	at hz.a(SourceFile:67)

Stephen, thanks for the update.
Yet discovered that this ticket was a duplicate of MC-502 , can you please attach there a crash report of version 1.4.5 ?

Sure Kumasasa, here it is:

---- Minecraft Crash Report ----
// You should try our sister game, Minceraft!

Time: 12/1/12 9:16 PM
Description: Ticking entity

java.lang.IllegalStateException: Entity is already tracked!
	at ii.a(SourceFile:72)
	at ii.a(SourceFile:50)
	at ij.a(SourceFile:24)
	at xv.a(SourceFile:842)
	at in.a(SourceFile:581)
	at xv.d(SourceFile:834)
	at gm.a(SourceFile:369)
	at lq.b(SourceFile:1492)
	at px.b(SourceFile:201)
	at amg.a(SourceFile:62)
	at lq.D(SourceFile:652)
	at lq.d(SourceFile:615)
	at px.j_(SourceFile:67)
	at xv.a(SourceFile:1317)
	at in.a(SourceFile:451)
	at xv.g(SourceFile:1296)
	at xv.h(SourceFile:1195)
	at in.h(SourceFile:363)
	at net.minecraft.server.MinecraftServer.r(SourceFile:751)
	at net.minecraft.server.MinecraftServer.q(SourceFile:686)
	at bdo.q(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:620)
	at fy.run(SourceFile:856)


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

-- Head --
Stacktrace:
	at ii.a(SourceFile:72)
	at ii.a(SourceFile:50)
	at ij.a(SourceFile:24)
	at xv.a(SourceFile:842)
	at in.a(SourceFile:581)
	at xv.d(SourceFile:834)
	at gm.a(SourceFile:369)
	at lq.b(SourceFile:1492)
	at px.b(SourceFile:201)
	at amg.a(SourceFile:62)
	at lq.D(SourceFile:652)
	at lq.d(SourceFile:615)
	at px.j_(SourceFile:67)
	at xv.a(SourceFile:1317)
	at in.a(SourceFile:451)
	at xv.g(SourceFile:1296)

-- Entity being ticked --
Details:
	Entity Type: Item (px)
	Entity ID: 114
	Name: item.tile.dirt
	Exact location: 100.00, 50.13, 0.00
	Block location: World: (100,50,0), Chunk: (at 4,3,0 in 6,0; contains blocks 96,0,0 to 111,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Momentum: -0.00, -0.17, -0.00
Stacktrace:
	at xv.h(SourceFile:1195)
	at in.h(SourceFile:363)

-- Affected level --
Details:
	Level name: Isle Creepis
	All players: 1 total; [iq['Knightstephen141'/77, l='Isle Creepis', x=100.00, y=49.00, z=0.00]]
	Chunk stats: ServerChunkCache: 441 Drop: 0
	Level seed: 7539544101188858510
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn 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)
	Level time: 0 game time, 0 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: ~~ERROR~~ NullPointerException: null
Stacktrace:
	at net.minecraft.server.MinecraftServer.r(SourceFile:751)
	at net.minecraft.server.MinecraftServer.q(SourceFile:686)
	at bdo.q(SourceFile:117)
	at net.minecraft.server.MinecraftServer.run(SourceFile:620)
	at fy.run(SourceFile:856)

-- System Details --
Details:
	Minecraft Version: 1.4.5
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_09, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 414369304 bytes (395 MB) / 514523136 bytes (490 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -Xms512m -Xmx1024m
	AABB Pool Size: 1301 (72856 bytes; 0 MB) allocated, 1301 (72856 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 1, tallocated: 63
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 107 (5992 bytes; 0 MB) allocated, 107 (5992 bytes; 0 MB) used
	Player Count: 1 / 8; [iq['Knightstephen141'/77, l='Isle Creepis', x=100.00, y=49.00, z=0.00]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.