10:51:54 [SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'bab' in plugin BuyAbilities v0.9.1
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:37)
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:128)
        at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:279)
        at net.minecraft.server.NetServerHandler.handleCommand(NetServerHandler.java:700)
        at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:667)
        at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:661)
        at net.minecraft.server.Packet3Chat.a(Packet3Chat.java:32)
        at net.minecraft.server.NetworkManager.a(NetworkManager.java:196)
        at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:75)
        at net.minecraft.server.NetworkListenThread.a(SourceFile:100)
        at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:377)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:292)
        at net.minecraft.server.ThreadServerApplication.run(SourceFile:394)
Caused by: java.lang.UnsupportedOperationException: Unsupported (or deprecated) operation, sorry dude.
        at ru.tehkode.permissions.compat.PermissionHandler.setCacheItem(PermissionHandler.java:443)
        at com.rcjrrjcr.bukkitplugins.util.permissionsinterface.PermYetiHandler.addPerm(PermYetiHandler.java:68)
        at com.rcjrrjcr.bukkitplugins.buyabilitiesplugin.AbilityManager.addPlayerAbility(AbilityManager.java:69)
        at com.rcjrrjcr.bukkitplugins.buyabilitiesplugin.AbilityManager.buyAbility(AbilityManager.java:100)
        at com.rcjrrjcr.bukkitplugins.buyabilitiesplugin.BuyAbilities.commandHandler(BuyAbilities.java:501)
        at com.rcjrrjcr.bukkitplugins.buyabilitiesplugin.BuyAbilities.onCommand(BuyAbilities.java:280)
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:35)
        ... 12 more