Bukkit

What steps will reproduce the problem?
1. Download MD
2. Give self mobdisguise.*
3. Type /md (then the animal you wanted)

What is the expected output? What do you see instead?
Expected: Turn into mob.
Instead: Internal Error
What version of the product are you using?
MobDisguise 1.81
Used for Minecraft 1.3.2
Do you have an error log of what happened?
[SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'md' in plugin MobDisguise v1.81
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:42)
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:168)
    at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:492)
    at net.minecraft.server.NetServerHandler.handleCommand(NetServerHandler.java:878)
    at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:825)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:807)
    at net.minecraft.server.Packet3Chat.handle(Packet3Chat.java:44)
    at net.minecraft.server.NetworkManager.b(NetworkManager.java:276)
    at net.minecraft.server.NetServerHandler.d(NetServerHandler.java:109)
    at net.minecraft.server.ServerConnection.b(SourceFile:35)
    at net.minecraft.server.DedicatedServerConnection.b(SourceFile:30)
    at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:581)
    at net.minecraft.server.DedicatedServer.q(DedicatedServer.java:212)
    at net.minecraft.server.MinecraftServer.p(MinecraftServer.java:474)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:406)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:539)
Caused by: java.lang.NoSuchFieldError: f
    at me.desmin88.mobdisguise.utils.PacketUtils.packetMaker(PacketUtils.java:146)
    at me.desmin88.mobdisguise.utils.PacketUtils.disguiseToAll(PacketUtils.java:61)
    at me.desmin88.mobdisguise.commands.MDCommand.onCommand(MDCommand.java:216)
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:40)
    ... 15 more

Please provide any additional information below.

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