[SEVERE] Could not pass event PlayerJoinEvent to MasterPromote
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:303)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:459)
	at net.minecraft.server.ServerConfigurationManager.c(ServerConfigurationManager.java:132)
	at net.minecraft.server.NetLoginHandler.b(NetLoginHandler.java:129)
	at net.minecraft.server.NetLoginHandler.a(NetLoginHandler.java:94)
	at net.minecraft.server.Packet1Login.handle(SourceFile:68)
	at net.minecraft.server.NetworkManager.b(NetworkManager.java:229)
	at net.minecraft.server.NetLoginHandler.a(NetLoginHandler.java:48)
	at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:61)
	at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:551)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:449)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)