07:36:54 [SEVERE] Could not pass event TraderTransactionEvent to Denizen v0.8-prerelease
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 net.dtl.citizens.trader.types.ServerTrader.simpleMode(ServerTrader.java:127)
        at net.dtl.citizens.trader.NpcEcoManager.onInventoryClick(NpcEcoManager.java:186)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.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)
        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 net.minecraft.server.v1_4_R1.PlayerConnection.a(PlayerConnection.java:1186)
        at net.minecraft.server.v1_4_R1.Packet102WindowClick.handle(SourceFile:31)
        at net.minecraft.server.v1_4_R1.NetworkManager.b(NetworkManager.java:290)
        at net.minecraft.server.v1_4_R1.PlayerConnection.d(PlayerConnection.java:113)
        at net.minecraft.server.v1_4_R1.ServerConnection.b(SourceFile:39)
        at net.minecraft.server.v1_4_R1.DedicatedServerConnection.b(SourceFile:30)
        at net.minecraft.server.v1_4_R1.MinecraftServer.r(MinecraftServer.java:598)
        at net.minecraft.server.v1_4_R1.DedicatedServer.r(DedicatedServer.java:224)
        at net.minecraft.server.v1_4_R1.MinecraftServer.q(MinecraftServer.java:494)
        at net.minecraft.server.v1_4_R1.MinecraftServer.run(MinecraftServer.java:427)
        at net.minecraft.server.v1_4_R1.ThreadServerApplication.run(SourceFile:849)
Caused by: java.lang.NoSuchMethodError: net.aufdemrand.denizen.utilities.DenizenAPI.getDenizenNPC(Lnet/citizensnpcs/api/npc/NPC;)Lnet/aufdemrand/denizen/npc/DenizenNPC;
        at net.dtl.citizens.trader.denizen.TraderTags.transactionResult(TraderTags.java:69)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.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)
        ... 24 more