Swords command

2013-11-09 23:21:29 [INFO] alfredo15 issued server command: /swords
2013-11-09 23:21:29 [SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'swords' in plugin mcMMO v1.4.07-dev2-b3324
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46)
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:192)
	at org.bukkit.craftbukkit.v1_6_R3.CraftServer.dispatchCommand(CraftServer.java:527)
	at net.minecraft.server.v1_6_R3.PlayerConnection.handleCommand(PlayerConnection.java:977)
	at net.minecraft.server.v1_6_R3.PlayerConnection.chat(PlayerConnection.java:888)
	at net.minecraft.server.v1_6_R3.PlayerConnection.a(PlayerConnection.java:835)
	at net.minecraft.server.v1_6_R3.Packet3Chat.handle(SourceFile:49)
	at org.spigotmc.netty.NettyNetworkManager.b(NettyNetworkManager.java:230)
	at net.minecraft.server.v1_6_R3.PlayerConnection.e(PlayerConnection.java:117)
	at net.minecraft.server.v1_6_R3.ServerConnection.b(SourceFile:37)
	at org.spigotmc.netty.NettyServerConnection.b(NettyServerConnection.java:132)
	at net.minecraft.server.v1_6_R3.MinecraftServer.t(MinecraftServer.java:594)
	at net.minecraft.server.v1_6_R3.DedicatedServer.t(DedicatedServer.java:240)
	at net.minecraft.server.v1_6_R3.MinecraftServer.s(MinecraftServer.java:483)
	at net.minecraft.server.v1_6_R3.MinecraftServer.run(MinecraftServer.java:415)
	at net.minecraft.server.v1_6_R3.ThreadServerApplication.run(SourceFile:583)
Caused by: java.lang.IllegalStateException: Cannot set scoreboard for invalid CraftPlayer
	at org.bukkit.craftbukkit.v1_6_R3.entity.CraftPlayer.setScoreboard(CraftPlayer.java:1011)
	at com.gmail.nossr50.util.scoreboards.ScoreboardManager.changeScoreboard(ScoreboardManager.java:315)
	at com.gmail.nossr50.util.scoreboards.ScoreboardManager.enablePlayerSkillScoreboard(ScoreboardManager.java:89)
	at com.gmail.nossr50.commands.skills.SkillCommand.onCommand(SkillCommand.java:78)
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44)
	... 15 more