Bukkit

What steps will reproduce the problem?
1.
2.
3.

What is the expected output? What do you see instead?
I was trying to setup the skyblock and had everything right and then suddenly I did /skyblock new and that Internal Server Error occured when trying to preform this command" came up. Now I love SkyBlock and would love to have this fixed thanks

What version of the product are you using?
1.5.1

Do you have an error log of what happened?
02.11 13:16:51 [Server] INFO ... 15 more
02.11 13:16:51 [Server] INFO at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44)
02.11 13:16:51 [Server] INFO at nz.Tzeentchful.SkyBlock.SkyblockCommand.onCommand(SkyblockCommand.java:40)
02.11 13:16:51 [Server] INFO at nz.Tzeentchful.SkyBlock.PartyManager.inParty(PartyManager.java:88)
02.11 13:16:51 [Server] INFO Caused by: java.lang.NullPointerException
02.11 13:16:51 [Server] INFO at net.minecraft.server.ThreadServerApplication.run(SourceFile:818)
02.11 13:16:51 [Server] INFO at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:419)
02.11 13:16:51 [Server] INFO at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:486)
02.11 13:16:51 [Server] INFO at net.minecraft.server.DedicatedServer.r(DedicatedServer.java:215)
02.11 13:16:51 [Server] INFO at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:569)
02.11 13:16:51 [Server] INFO at net.minecraft.server.DedicatedServerConnection.b(SourceFile:30)
02.11 13:16:51 [Server] INFO at net.minecraft.server.ServerConnection.b(SourceFile:35)
02.11 13:16:51 [Server] INFO at net.minecraft.server.NetServerHandler.d(NetServerHandler.java:111)
02.11 13:16:51 [Server] INFO at net.minecraft.server.NetworkManager.b(NetworkManager.java:282)
02.11 13:16:51 [Server] INFO at net.minecraft.server.Packet3Chat.handle(Packet3Chat.java:44)
02.11 13:16:51 [Server] INFO at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:806)
02.11 13:16:51 [Server] INFO at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:824)
02.11 13:16:51 [Server] INFO at net.minecraft.server.NetServerHandler.handleCommand(NetServerHandler.java:911)
02.11 13:16:51 [Server] INFO at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:504)
02.11 13:16:51 [Server] INFO at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:185)
02.11 13:16:51 [Server] INFO at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46)
02.11 13:16:51 [Server] INFO org.bukkit.command.CommandException: Unhandled exception executing command 'skyblock' in plugin SkyBlockCo-Op v1.5

Please provide any additional information below.