19:25:43 [SEVERE] Could not pass event PlayerInteractEvent to GPRealEstate v0.52b
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:26)
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:479)
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:464)
        at org.bukkit.craftbukkit.v1_5_R2.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:181)
        at net.minecraft.server.v1_5_R2.PlayerInteractManager.interact(PlayerInteractManager.java:375)
        at net.minecraft.server.v1_5_R2.PlayerConnection.a(PlayerConnection.java:632)
        at net.minecraft.server.v1_5_R2.Packet15Place.handle(SourceFile:58)
        at org.spigotmc.netty.NettyNetworkManager.b(NettyNetworkManager.java:176)
        at net.minecraft.server.v1_5_R2.PlayerConnection.d(PlayerConnection.java:110)
        at net.minecraft.server.v1_5_R2.ServerConnection.b(SourceFile:35)
        at org.spigotmc.netty.NettyServerConnection.b(NettyServerConnection.java:66)
        at net.minecraft.server.v1_5_R2.MinecraftServer.r(MinecraftServer.java:580)
        at net.minecraft.server.v1_5_R2.DedicatedServer.r(DedicatedServer.java:229)
        at net.minecraft.server.v1_5_R2.MinecraftServer.q(MinecraftServer.java:469)
        at net.minecraft.server.v1_5_R2.MinecraftServer.run(MinecraftServer.java:401)
        at net.minecraft.server.v1_5_R2.ThreadServerApplication.run(SourceFile:573)
Caused by: java.lang.NoSuchMethodError: me.ryanhamshire.GriefPrevention.Claim.clearPermissions()V
        at com.github.leezallen.GPRealEstate.GPREListener.onSignInteract(GPREListener.java:259)
        at sun.reflect.GeneratedMethodAccessor7.invoke(Unknown Source)
        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:425)
        ... 17 more