gistfile1.java

18:28:21 [SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'ch' in plugin MCNSAChallenges v1.0.1
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46)
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:189)
	at org.bukkit.craftbukkit.v1_6_R2.CraftServer.dispatchCommand(CraftServer.java:523)
	at net.minecraft.server.v1_6_R2.PlayerConnection.handleCommand(PlayerConnection.java:962)
	at net.minecraft.server.v1_6_R2.PlayerConnection.chat(PlayerConnection.java:880)
	at net.minecraft.server.v1_6_R2.PlayerConnection.a(PlayerConnection.java:837)
	at net.minecraft.server.v1_6_R2.Packet3Chat.handle(SourceFile:49)
	at net.minecraft.server.v1_6_R2.NetworkManager.b(NetworkManager.java:296)
	at net.minecraft.server.v1_6_R2.PlayerConnection.e(PlayerConnection.java:116)
	at net.minecraft.server.v1_6_R2.ServerConnection.b(SourceFile:37)
	at net.minecraft.server.v1_6_R2.DedicatedServerConnection.b(SourceFile:30)
	at net.minecraft.server.v1_6_R2.MinecraftServer.t(MinecraftServer.java:590)
	at net.minecraft.server.v1_6_R2.DedicatedServer.t(DedicatedServer.java:226)
	at net.minecraft.server.v1_6_R2.MinecraftServer.s(MinecraftServer.java:486)
	at net.minecraft.server.v1_6_R2.MinecraftServer.run(MinecraftServer.java:419)
	at net.minecraft.server.v1_6_R2.ThreadServerApplication.run(SourceFile:582)
Caused by: java.lang.StringIndexOutOfBoundsException: String index out of range: 1
	at java.lang.String.substring(String.java:1907)
	at com.matejdro.bukkit.mcnsa.challenges.Util.hasPermission(Util.java:90)
	at com.matejdro.bukkit.mcnsa.challenges.usercommands.BaseUserCommand.hasPermission(BaseUserCommand.java:52)
	at com.matejdro.bukkit.mcnsa.challenges.usercommands.BaseUserCommand.execute(BaseUserCommand.java:41)
	at com.matejdro.bukkit.mcnsa.challenges.MCNSAChallenges.onCommand(MCNSAChallenges.java:149)
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44)
	... 15 more