Bukkit

What steps will reproduce the problem?
1.I create arena
2.nothing to say
3.I retars the server and ERROR

What is the expected output? What do you see instead?
I can't join arena and i

What version of the product are you using?
v.2.4.0

Do you have an error log of what happened?
[10:08:20]     [Server thread/INFO] : plugins/Quake/Stuff/Armors/ArmorRED.yml found implementation
[10:08:20]     [Server thread/WARN] : plugins/Quake/Stuff/Armors/ArmorRED.yml
[10:08:20]     [Server thread/INFO] : plugins/Quake/Stuff/Hats/JackOHat.yml found implementation
[10:08:20]     [Server thread/WARN] : plugins/Quake/Stuff/Hats/JackOHat.yml
[10:08:20]     [Server thread/ERROR] : 0 not a valid Material. Example: APPLE
[10:08:20]     [Server thread/INFO] : plugins/Quake/Stuff/Hats/Geekpower14.yml found implementation
[10:08:20]     [Server thread/WARN] : plugins/Quake/Stuff/Hats/Geekpower14.yml
[10:08:20]     [Server thread/INFO] : salsal13015 issued server command: /quake reload
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:457)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:545)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:250)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:655)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.ServerConnection.c(SourceFile:134)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:146)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.PacketPlayInChat.handle(PacketPlayInChat.java:47)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.PacketPlayInChat.a(PacketPlayInChat.java:28)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java:814)
[10:08:18]     [Server thread/WARN] : at net.minecraft.server.v1_7_R1.PlayerConnection.handleCommand(PlayerConnection.java:952)
[10:08:18]     [Server thread/WARN] : at org.bukkit.craftbukkit.v1_7_R1.CraftServer.dispatchCommand(CraftServer.java:683)
[10:08:18]     [Server thread/WARN] : at us.Myles.PWP.FakeSimpleCommandMap.dispatch(FakeSimpleCommandMap.java:94)
[10:08:18]     [Server thread/WARN] : at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44)
[10:08:18]     [Server thread/WARN] : at com.Geekpower14.Quake.Commands.MyCommandExecutor.onCommand(MyCommandExecutor.java:128)
[10:08:18]     [Server thread/WARN] : at com.Geekpower14.Quake.Commands.LeaveCommand.onCommand(LeaveCommand.java:30)
[10:08:18]     [Server thread/WARN] : at com.Geekpower14.Quake.Arena.TArena.leaveArena(TArena.java:349)
[10:08:18]     [Server thread/WARN] : at org.bukkit.craftbukkit.v1_7_R1.entity.CraftEntity.teleport(CraftEntity.java:200)
[10:08:18]     [Server thread/WARN] : at org.bukkit.craftbukkit.v1_7_R1.entity.CraftPlayer.teleport(CraftPlayer.java:456)
[10:08:18]     [Server thread/WARN] : java.lang.NullPointerException

Please provide any additional information below.