Bukkit

What steps will reproduce the problem?
1. Install Duckshop and dependencies
2.
3.

What is the expected output? What do you see instead?
I expect the command /ds or /duckshop to work. Instead I get an internal error.

What version of the product are you using?
32

Do you have an error log of what happened?

2012-07-06 22:53:29 [SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'duckshop' in plugin DuckShop v32
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:42)
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:166)
    at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:479)
    at net.minecraft.server.NetServerHandler.handleCommand(NetServerHandler.java:821)
    at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:781)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:764)
    at net.minecraft.server.Packet3Chat.handle(Packet3Chat.java:34)
    at net.minecraft.server.NetworkManager.b(NetworkManager.java:229)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:113)
    at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:78)
    at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:567)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:459)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
    at java.util.ArrayList$SubList.rangeCheck(Unknown Source)
    at java.util.ArrayList$SubList.get(Unknown Source)
    at tk.allele.util.commands.CommandDispatcher.execute(CommandDispatcher.java:38)
    at tk.allele.util.commands.CommandDispatcher.onCommand(CommandDispatcher.java:56)
    at tk.allele.duckshop.DuckShop.onCommand(DuckShop.java:81)
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:40)
    ... 12 more
]

Please provide any additional information below.