NPE at VaultHook.isLoaded

[Nerade]

Since a few days without any change (at least I don't remember) every event recognized by NoItem causes NPEs like following one:

2013-08-11 22:33:28 [SEVERE] Could not pass event PlayerItemHeldEvent to NoItem v3.0.3-242
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:394)
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 iv.a(NetServerHandler.java:1073)
at er.a(Packet16BlockItemSwitch.java:40)
at cg.b(TcpConnection.java:467)
at iv.d(NetServerHandler.java:220)
at iw.b(NetworkListenThread.java:57)
at ht.b(DedicatedServerListenThread.java:34)
at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:981)
at ho.r(DedicatedServer.java:309)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:857)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:744)
at fy.run(ThreadMinecraftServer.java:16)
Caused by: java.lang.NullPointerException
at net.worldoftomorrow.noitem.permissions.VaultHook.isLoaded(Unknown Source)
at net.worldoftomorrow.noitem.permissions.PermMan.checkVault(Unknown Source)
at net.worldoftomorrow.noitem.permissions.PermMan.check(Unknown Source)
at net.worldoftomorrow.noitem.permissions.PermMan.has(Unknown Source)
at net.worldoftomorrow.noitem.events.Handlers.handleItemHeld(Unknown Source)
at net.worldoftomorrow.noitem.events.Listeners.onItemHeld(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:392)
... 14 more

I don't really understand why this is possible because the variable "instance" must have a value set by the constructor?!