2013-06-10 10:34:26 [SEVERE] Could not pass event CreatureSpawnEvent to MineZ v1.5
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:427)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
	at org.bukkit.craftbukkit.v1_5_R3.event.CraftEventFactory.callCreatureSpawnEvent(CraftEventFactory.java:235)
	at net.minecraft.server.v1_5_R3.World.addEntity(World.java:924)
	at net.minecraft.server.v1_5_R3.SpawnerCreature.spawnEntities(SpawnerCreature.java:159)
	at net.minecraft.server.v1_5_R3.WorldServer.doTick(WorldServer.java:186)
	at net.minecraft.server.v1_5_R3.MinecraftServer.r(MinecraftServer.java:555)
	at net.minecraft.server.v1_5_R3.DedicatedServer.r(DedicatedServer.java:226)
	at net.minecraft.server.v1_5_R3.MinecraftServer.q(MinecraftServer.java:477)
	at net.minecraft.server.v1_5_R3.MinecraftServer.run(MinecraftServer.java:410)
	at net.minecraft.server.v1_5_R3.ThreadServerApplication.run(SourceFile:573)
Caused by: java.lang.NoClassDefFoundError: com/sk89q/worldguard/bukkit/WorldGuardPlugin
	at com.jordair.gmail.MyZ.Listeners.mobSpawnListener.onSpawn(mobSpawnListener.java:50)
	at sun.reflect.GeneratedMethodAccessor20.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:425)
	... 12 more