[14:43:37] [Server thread/ERROR]: Could not pass event PlayerInteractEvent to GPRealEstate v1.4.1
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:299) ~[spigot179.jar:git-Spigot-1543]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot179.jar:git-Spigot-1543]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot179.jar:git-Spigot-1543]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot179.jar:git-Spigot-1543]
        at org.bukkit.craftbukkit.v1_7_R3.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:243) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.PlayerInteractManager.interact(PlayerInteractManager.java:375) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.PlayerConnection.a(PlayerConnection.java:657) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.PacketPlayInBlockPlace.a(SourceFile:60) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.PacketPlayInBlockPlace.handle(SourceFile:9) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.NetworkManager.a(NetworkManager.java:184) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.ServerConnection.c(ServerConnection.java:81) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.MinecraftServer.v(MinecraftServer.java:731) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.DedicatedServer.v(DedicatedServer.java:284) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.MinecraftServer.u(MinecraftServer.java:584) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.MinecraftServer.run(MinecraftServer.java:490) [spigot179.jar:git-Spigot-1543]
        at net.minecraft.server.v1_7_R3.ThreadServerApplication.run(SourceFile:628) [spigot179.jar:git-Spigot-1543]
Caused by: java.lang.NoSuchMethodError: me.ryanhamshire.GriefPrevention.Claim.clearPermissions()Z
        at me.GuyB790.GPR.GPREListener.onSignInteract(GPREListener.java:374) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_20]
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_20]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_20]
        at java.lang.reflect.Method.invoke(Method.java:483) ~[?:1.8.0_20]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:296) ~[spigot179.jar:git-Spigot-1543]
        ... 15 more