Bukkit

What steps will reproduce the problem?
1. I keep seeing this in error logs: [15:02:42] [Server thread/ERROR]: Could not pass event InventoryCreativeEvent to MoneyDrop v2.2.0

I see it in error logs like once or twice a day; I will paste the whole log portion below.

What is the expected output? What do you see instead?
I don't see anything in game.

What version of the product are you using?
2.2.0

Do you have an error log of what happened?

[15:02:32] [Server thread/INFO]: [WorldBorder] [Fill] Saving the world to disk, just to be on the safe side. (free mem: 5431 MB)
[15:02:36] [Server thread/INFO]: EmpathyHeals issued server command: /plotme home
[15:02:36] [Async Chat Thread - #14/INFO]: [Survival] [Seeker] she died
[15:02:37] [Server thread/INFO]: [WorldBorder] [Fill] 50 more chunks processed (45372 total, ~4.3%) (free mem: 5309 MB)
[15:02:42] [Server thread/INFO]: [WorldBorder] [Fill] 50 more chunks processed (45422 total, ~4.3%) (free mem: 5393 MB)
[15:02:42] [Server thread/ERROR]: Could not pass event InventoryCreativeEvent to MoneyDrop v2.2.0
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:320) ~[custom_server.jar:git-Spigot-1338]
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[custom_server.jar:git-Spigot-1338]
at org.bukkit.plugin.TimedRegisteredListener.callEvent(TimedRegisteredListener.java:30) ~[custom_server.jar:git-Spigot-1338]
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:487) [custom_server.jar:git-Spigot-1338]
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:472) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java:1525) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.PacketPlayInSetCreativeSlot.a(SourceFile:23) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.PacketPlayInSetCreativeSlot.handle(SourceFile:9) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:147) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.ServerConnection.c(ServerConnection.java:77) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:700) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:273) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:562) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:469) [custom_server.jar:git-Spigot-1338]
at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617) [custom_server.jar:git-Spigot-1338]
Caused by: java.lang.NullPointerException
at me.drakespirit.plugins.moneydrop.EventListener.handleInventoryClicks(EventListener.java:331) ~[?:?]
at sun.reflect.GeneratedMethodAccessor81.invoke(Unknown Source) ~[?:?]

Please provide any additional information below.