Bukkit

What steps will reproduce the problem?
1. Creating a region.
2. Letting the server run.
3. PlayerRegionEvent occurs.

What is the expected output? What do you see instead?
I expected no errors. But instead I got this error: Could not pass event PlayerInRegionEvent to HeroStronghold v0.6.1-b000

What version of the product are you using?
Latest version of Herostronghold, uploaded on June 03 2013. Craftbukkit 1.6.4-R2.0

Do you have an error log of what happened?
12:11:53 [SEVERE] Could not pass event PlayerInRegionEvent to HeroStronghold v0.6.1-b000
org.bukkit.event.EventException
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:427)
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
    at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
    at multitallented.redcastlemedia.bukkit.herostronghold.checkregiontask.CheckPlayerInRegionThread.run(CheckPlayerInRegionThread.java:32)
    at multitallented.redcastlemedia.bukkit.herostronghold.checkregiontask.CheckRegionTask.run(CheckRegionTask.java:55)
    at org.bukkit.craftbukkit.v1_6_R3.scheduler.CraftTask.run(CraftTask.java:53)
    at org.bukkit.craftbukkit.v1_6_R3.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:345)
    at net.minecraft.server.v1_6_R3.MinecraftServer.t(MinecraftServer.java:524)
    at net.minecraft.server.v1_6_R3.DedicatedServer.t(DedicatedServer.java:227)
    at net.minecraft.server.v1_6_R3.MinecraftServer.s(MinecraftServer.java:488)
    at net.minecraft.server.v1_6_R3.MinecraftServer.run(MinecraftServer.java:421)
    at net.minecraft.server.v1_6_R3.ThreadServerApplication.run(SourceFile:583)
Caused by: java.lang.NoSuchMethodError: com.herocraftonline.heroes.characters.Hero.getHealth()I
    at main.java.multitallented.plugins.herostronghold.effects.EffectGainHealth$IntruderListener.onCustomEvent(EffectGainHealth.java:50)
    at sun.reflect.GeneratedMethodAccessor192.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:425)
    ... 12 more

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