22:43:53 [SEVERE] Could not pass event PlayerInteractEvent to AntiInvisible v1.0
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.TimedRegisteredListener.callEvent(TimedRegisteredListener.java:30)
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:478)
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:463)
        at org.bukkit.craftbukkit.v1_5_R3.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:190)
        at net.minecraft.server.v1_5_R3.PlayerInteractManager.interact(PlayerInteractManager.java:371)
        at net.minecraft.server.v1_5_R3.PlayerConnection.a(PlayerConnection.java:637)
        at net.minecraft.server.v1_5_R3.Packet15Place.handle(SourceFile:58)
        at org.spigotmc.netty.NettyNetworkManager.b(NettyNetworkManager.java:218)
        at net.minecraft.server.v1_5_R3.PlayerConnection.d(PlayerConnection.java:115)
        at net.minecraft.server.v1_5_R3.ServerConnection.b(SourceFile:35)
        at org.spigotmc.MultiplexingServerConnection.b(MultiplexingServerConnection.java:72)
        at net.minecraft.server.v1_5_R3.MinecraftServer.r(MinecraftServer.java:583)
        at net.minecraft.server.v1_5_R3.DedicatedServer.r(DedicatedServer.java:227)
        at net.minecraft.server.v1_5_R3.MinecraftServer.q(MinecraftServer.java:472)
        at net.minecraft.server.v1_5_R3.MinecraftServer.run(MinecraftServer.java:404)
        at net.minecraft.server.v1_5_R3.ThreadServerApplication.run(SourceFile:573)
Caused by: java.lang.NullPointerException
        at com.drtshock.antiinvisibility.AntiInvisibility.onDrink(AntiInvisibility.java:36)
        at sun.reflect.GeneratedMethodAccessor106.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)
        ... 17 more