Bukkit

What steps will reproduce the problem?
1. 3 Player on Bukkit Server V.1.7.2
2. I'm Serverhost play with Lan IP on the Server, my friends with Internet-IP
3. I can without OP and in the same Permissionsgroup add friends, but they two can't add people. We had give OP my friends, no changes...

pls fix.

What is the expected output? What do you see instead?

What version of the product are you using?
1.5

Do you have an error log of what happened?
[23:49:47 INFO]: ischkur issued server command: /ProtectBlock-Friends add Chacytay
[23:49:47 ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'prot
ectblock-friends' in plugin ProtectBlock v1.5
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[cra
ftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:19
6) ~[craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at org.bukkit.craftbukkit.v1_7_R1.CraftServer.dispatchCommand(CraftServe
r.java:542) ~[craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.PlayerConnection.handleCommand(PlayerCon
nection.java:932) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java
:814) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.PacketPlayInChat.a(PacketPlayInChat.java
:28) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.PacketPlayInChat.handle(PacketPlayInChat
.java:47) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:146
) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.ServerConnection.c(SourceFile:134) [craf
tbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:6
55) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:2
50) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:5
45) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java
:457) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:6
17) [craftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
Caused by: java.lang.NullPointerException
        at com.yianni000.ProtectBlock.Friends.addChild(Friends.java:76) ~[?:?]
        at com.yianni000.ProtectBlock.ProtectBlock.onCommand(ProtectBlock.java:2
56) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[cra
ftbukkit-1.7.2-R0.2.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        ... 13 more

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