Magic Error

[19:18:24 ERROR]: Could not pass event PlayerInteractEvent to Magic v4.5.5
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:302) ~[spigot.jar:git-Spigot-1649]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.jav
a:62) ~[spigot.jar:git-Spigot-1649]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.j
ava:514) [spigot.jar:git-Spigot-1649]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.j
ava:499) [spigot.jar:git-Spigot-1649]
        at org.bukkit.craftbukkit.v1_7_R4.event.CraftEventFactory.callPlayerInte
ractEvent(CraftEventFactory.java:242) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.PlayerInteractManager.dig(PlayerInteract
Manager.java:103) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.PlayerConnection.a(PlayerConnection.java
:552) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.PacketPlayInBlockDig.a(PacketPlayInBlock
Dig.java:41) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.PacketPlayInBlockDig.handle(PacketPlayIn
BlockDig.java:65) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.NetworkManager.a(NetworkManager.java:186
) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.ServerConnection.c(ServerConnection.java
:81) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.MinecraftServer.v(MinecraftServer.java:7
34) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.DedicatedServer.v(DedicatedServer.java:2
89) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.MinecraftServer.u(MinecraftServer.java:5
84) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java
:490) [spigot.jar:git-Spigot-1649]
        at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:6
28) [spigot.jar:git-Spigot-1649]
Caused by: java.lang.NoClassDefFoundError: Could not initialize class net.milkbo
wl.vault.item.Items
        at com.elmakers.mine.bukkit.integration.VaultController.getItemName(Vaul
tController.java:96) ~[?:?]
        at com.elmakers.mine.bukkit.block.MaterialAndData.getName(MaterialAndDat
a.java:593) ~[?:?]
        at com.elmakers.mine.bukkit.block.MaterialAndData.getName(MaterialAndDat
a.java:579) ~[?:?]
        at com.elmakers.mine.bukkit.block.MaterialAndData.getMaterialName(Materi
alAndData.java:575) ~[?:?]
        at com.elmakers.mine.bukkit.spell.TargetingSpell.getDisplayMaterialName(
TargetingSpell.java:852) ~[?:?]
        at com.elmakers.mine.bukkit.spell.BaseSpell.getMessage(BaseSpell.java:10
64) ~[?:?]
        at com.elmakers.mine.bukkit.spell.TargetingSpell.getMessage(TargetingSpe
ll.java:99) ~[?:?]
        at com.elmakers.mine.bukkit.spell.BlockSpell.getMessage(BlockSpell.java:
75) ~[?:?]
        at com.elmakers.mine.bukkit.spell.BaseSpell.getMessage(BaseSpell.java:10
49) ~[?:?]
        at com.elmakers.mine.bukkit.spell.builtin.AnimateSpell.onCast(AnimateSpe
ll.java:145) ~[?:?]
        at com.elmakers.mine.bukkit.spell.BaseSpell.finalizeCast(BaseSpell.java:
1018) ~[?:?]
        at com.elmakers.mine.bukkit.spell.BaseSpell.cast(BaseSpell.java:952) ~[?
:?]
        at com.elmakers.mine.bukkit.spell.BaseSpell.cast(BaseSpell.java:1384) ~[
?:?]
        at com.elmakers.mine.bukkit.wand.Wand.cast(Wand.java:2818) ~[?:?]
        at com.elmakers.mine.bukkit.magic.MagicController.onPlayerInteract(Magic
Controller.java:2863) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0
_31]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0
_31]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1
.8.0_31]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_31]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:298) ~[spigot.jar:git-Spigot-1649]