Bukkit

What steps will reproduce the problem?
1.Making a planter
2.Putting required things in
3.Flipping lever

What is the expected output? What do you see instead?
It planting and stuff                        This error

What version of the product are you using?
v4.1.13

Do you have an error log of what happened?
yeah:
[21:40:52 ERROR]: Could not pass event PlayerInteractEvent to MachinaCore v4.1.1
4
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:302) ~[craftbukkit.jar:git-Bukkit-f27339c]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.jav
a:62) ~[craftbukkit.jar:git-Bukkit-f27339c]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.j
ava:501) [craftbukkit.jar:git-Bukkit-f27339c]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.j
ava:486) [craftbukkit.jar:git-Bukkit-f27339c]
        at org.bukkit.craftbukkit.v1_8_R3.event.CraftEventFactory.callPlayerInte
ractEvent(CraftEventFactory.java:210) [craftbukkit.jar:git-Bukkit-f27339c]
        at net.minecraft.server.v1_8_R3.PlayerInteractManager.interact(PlayerInt
eractManager.java:462) [craftbukkit.jar:git-Bukkit-f27339c]
        at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java
:705) [craftbukkit.jar:git-Bukkit-f27339c]
        at net.minecraft.server.v1_8_R3.PacketPlayInBlockPlace.a(PacketPlayInBlo
ckPlace.java:52) [craftbukkit.jar:git-Bukkit-f27339c]
        at net.minecraft.server.v1_8_R3.PacketPlayInBlockPlace.a(PacketPlayInBlo
ckPlace.java:1) [craftbukkit.jar:git-Bukkit-f27339c]
        at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:1
3) [craftbukkit.jar:git-Bukkit-f27339c]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [
?:1.8.0_51]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_51]
        at net.minecraft.server.v1_8_R3.SystemUtils.a(SystemUtils.java:19) [craf
tbukkit.jar:git-Bukkit-f27339c]
        at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:6
76) [craftbukkit.jar:git-Bukkit-f27339c]
        at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:3
35) [craftbukkit.jar:git-Bukkit-f27339c]
        at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:6
32) [craftbukkit.jar:git-Bukkit-f27339c]
        at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java
:540) [craftbukkit.jar:git-Bukkit-f27339c]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_51]
Caused by: java.lang.NoClassDefFoundError: Could not initialize class me.lyneira
.MachinaCore.Fuel
        at me.lyneira.MachinaPlanter.Planter.<init>(Planter.java:63) ~[?:?]
        at me.lyneira.MachinaPlanter.Blueprint.detect(Blueprint.java:82) ~[?:?]
        at me.lyneira.MachinaCore.MachinaCore.onLever(MachinaCore.java:71) ~[?:?
]
        at me.lyneira.MachinaCore.MachinaCoreListener.playerInteract(MachinaCore
Listener.java:49) ~[?:?]
        at sun.reflect.GeneratedMethodAccessor166.invoke(Unknown Source) ~[?:?]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1
.8.0_51]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_51]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:300) ~[craftbukkit.jar:git-Bukkit-f27339c]
        ... 17 more

Please provide any additional information below.

Im not sure if the other things work though