Bukkit

What steps will reproduce the problem?
1. Placing/Braking a block

What is the expected output? What do you see instead?
An achievement to pop up in the text, instead nothing happens except a severe error in the console.

What version of the product are you using?
1.4 (With vault)

Do you have an error log of what happened?
2011-12-09 18:58:33 [SEVERE] Could not pass event BLOCK_PLACE to Achievement
java.lang.NoClassDefFoundError: net/milkbowl/vault/permission/Permission
    at com.modcrafting.achievement.Achievement.setupPermissions(Achievement.java:107)
    at com.modcrafting.achievement.listener.AchieveBlockListener.onBlockPlace(AchieveBlockListener.java:74)
    at org.bukkit.plugin.java.JavaPluginLoader$32.execute(JavaPluginLoader.java:478)
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:58)
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:339)
    at org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPlaceEvent(CraftEventFactory.java:100)
    at org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPlaceEvent(CraftEventFactory.java:84)
    at net.minecraft.server.ItemBlock.a(ItemBlock.java:97)
    at net.minecraft.server.ItemStack.placeItem(ItemStack.java:69)
    at net.minecraft.server.ItemInWorldManager.interact(ItemInWorldManager.java:282)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:592)
    at net.minecraft.server.Packet15Place.a(SourceFile:39)
    at net.minecraft.server.NetworkManager.b(NetworkManager.java:226)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:92)
    at org.getspout.spout.SpoutNetServerHandler.a(SpoutNetServerHandler.java:550)
    at net.minecraft.server.NetworkListenThread.a(SourceFile:108)
    at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:516)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:414)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:457)
Caused by: java.lang.ClassNotFoundException: net.milkbowl.vault.permission.Permission
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:36)
    at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:24)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    ... 19 more
2011-12-09 18:58:39 [SEVERE] Could not pass event BLOCK_BREAK to Achievement
java.lang.NoClassDefFoundError: net/milkbowl/vault/permission/Permission
    at com.modcrafting.achievement.Achievement.setupPermissions(Achievement.java:107)
    at com.modcrafting.achievement.listener.AchieveBlockListener.onBlockBreak(AchieveBlockListener.java:28)
    at org.bukkit.plugin.java.JavaPluginLoader$40.execute(JavaPluginLoader.java:534)
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:58)
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:339)
    at net.minecraft.server.ItemInWorldManager.c(ItemInWorldManager.java:201)
    at net.minecraft.server.ItemInWorldManager.dig(ItemInWorldManager.java:98)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:497)
    at org.getspout.spout.SpoutNetServerHandler.a(SpoutNetServerHandler.java:208)
    at net.minecraft.server.Packet14BlockDig.a(SourceFile:43)
    at net.minecraft.server.NetworkManager.b(NetworkManager.java:226)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:92)
    at org.getspout.spout.SpoutNetServerHandler.a(SpoutNetServerHandler.java:550)
    at net.minecraft.server.NetworkListenThread.a(SourceFile:108)
    at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:516)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:414)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:457)

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