Essentials Error

org.bukkit.command.CommandException: Unhandled exception executing command 'tp'
in plugin Essentials v2.11.1
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46)
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:18
9)
        at org.bukkit.craftbukkit.v1_5_R3.CraftServer.dispatchCommand(CraftServe
r.java:555)
        at net.minecraft.network.NetServerHandler.func_72566_d(NetServerHandler.
java:1390)
        at net.minecraft.network.NetServerHandler.chat(NetServerHandler.java:125
0)
        at net.minecraft.network.NetServerHandler.func_72481_a(NetServerHandler.
java:1176)
        at net.minecraft.network.packet.Packet3Chat.func_73279_a(Packet3Chat.jav
a:60)
        at net.minecraft.network.TcpConnection.func_74428_b(TcpConnection.java:4
42)
        at net.minecraft.network.NetServerHandler.func_72570_d(NetServerHandler.
java:223)
        at net.minecraft.network.NetworkListenThread.func_71747_b(NetworkListenT
hread.java:53)
        at net.minecraft.server.dedicated.DedicatedServerListenThread.func_71747
_b(SourceFile:30)
        at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.jav
a:865)
        at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(Dedicated
Server.java:320)
        at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.jav
a:732)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:614)
        at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:573)
Caused by: java.lang.NullPointerException
        at com.earth2me.essentials.Essentials.onCommandEssentials(Essentials.jav
a:339)
        at com.earth2me.essentials.Essentials.onCommand(Essentials.java:330)
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44)
        ... 15 more