[0.5.3] Attempting to place sign on top of sequencer or timer in SMP on a server causes issue

[Cprossu]

Title: [0.5.3] Attempting to place sign on top of sequencer or timer in SMP on a server causes issue

Version: 0.5.1

OS: Microsoft Windows 7 Professional x64 on client Microsoft Windows XP 32bit on server

Java Version: java version "1.7.0_10" Java SE Runtime Environment (build 1.7.0_10-b18) Java HotSpot 64-Bit Server VM (build 23.6-b04, mixed mode)

Description of Problem:

When logged into my multiplayer server, when I attempted to put a sign on top of a sequencer it caused me to be kicked from my server and yielded an error

Error Messages:

"Disconnected by Server"

"Internal server error"

Error Log:

Server Log

2013-01-21 19:27:40 [sEVERE] [ForgeModLoader] A critical server error occured ha

ndling a packet, kicking 18

java.lang.NullPointerException

        at iv.a(NetServerHandler.java:639)

        at fk.a(SourceFile:58)

        at cg.b(TcpConnection.java:458)

        at iv.d(NetServerHandler.java:136)

        at iw.b(NetworkListenThread.java:57)

        at ht.b(SourceFile:30)

        at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:703)

        at ho.r(DedicatedServer.java:270)

        at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:599)

        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:497)

        at fy.run(SourceFile:849)

2013-01-21 19:27:40 [WARNING] [Minecraft] Failed to handle packet for warblade99

/192.168.1.165: java.lang.NullPointerException

java.lang.NullPointerException

        at iv.a(NetServerHandler.java:639)

        at fk.a(SourceFile:58)

        at cg.b(TcpConnection.java:458)

        at iv.d(NetServerHandler.java:136)

        at iw.b(NetworkListenThread.java:57)

        at ht.b(SourceFile:30)

        at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:703)

        at ho.r(DedicatedServer.java:270)

        at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:599)

        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:497)

        at fy.run(SourceFile:849)

2013-01-21 19:27:40 [iNFO] [sTDOUT] Unloading Player: warblade99



Client log is too horrifying to post in this form

http://pastebin.com/3AmnvjeM