Internal Error: ArrayIndexOutOfBoundsException: 6

Hello people. I currrently am using Bukkit 1000 on my server. Everytime I start the server and one person joins, I get the internal error message shown below. A full list of plugins I use is listed below the error. Helping me in this matter would be greatly appreciated by myself and my staff. Thank you very much for your time.

~Vince

1. What OS are you using? Windows Vista Home Premium
2. What architecture is the OS you are running? 32 bit
3. What version and architecture is your java install? 1.6.0_24
4. Are you running any wrappers? Hamachi
5. What build of CraftBukkit are you running? 1000

Code:

17:35:24 [INFO] Done (0.827s)! For help, type "help" or "?"
17:36:05 [INFO] Spartan_V23 [/5.242.145.102:57156] logged in with entity id 13 a
t ([world] 151.2619854797607, 101.0, 36.63793192678639)
17:36:32 [WARNING] Failed to handle packet: java.lang.ArrayIndexOutOfBoundsExcep
tion: 6
java.lang.ArrayIndexOutOfBoundsException: 6
        at net.minecraft.server.BlockPistonExtension.doPhysics(SourceFile:189)
        at net.minecraft.server.World.k(World.java:453)
        at net.minecraft.server.World.applyPhysics(World.java:429)
        at net.minecraft.server.World.update(World.java:401)
        at net.minecraft.server.ItemBlock.a(ItemBlock.java:100)
        at net.minecraft.server.ItemStack.placeItem(ItemStack.java:56)
        at net.minecraft.server.ItemInWorldManager.interact(ItemInWorldManager.j
ava:223)
        at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:553)
        at net.minecraft.server.Packet15Place.a(SourceFile:57)
        at net.minecraft.server.NetworkManager.b(NetworkManager.java:226)
        at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:85)
        at net.minecraft.server.NetworkListenThread.a(SourceFile:105)
        at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:451)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:361)
        at net.minecraft.server.ThreadServerApplication.run(SourceFile:422)

Complete List of Plugins I Use...

Show Spoiler Hide Spoiler

1) Auto Message.
2) Command Book
3) Command Signs
4) God Powers
5) Helios
6) Basic Herobrine
7) Heroic Death
8) mcMMO
9) Mob Arena
10) Mob Disguise
11) No Spawn
12) No Weather
13) Permissions 3.1.5
14) Spout
15) Spyer Admin, Spyer Fun, Spyer Admin Commands
16) Supply Sign
17) Waypoint 1.4.5
18) Wireless Redstone
19) World Edit

I do make sure all the plugins I use are up-to-date
and/or function properly on my server before installation.

Please people, I have about 25 people barking at me to get this server running. I am at a stand still with this issue.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.