19:38:14 [SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'manuadd' in plugin GroupManager v2.0 (2.10.1) (Phoenix)
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:42)
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:166)
	at forge.bukkit.ForgeCommandMap.dispatch(ForgeCommandMap.java:55)
	at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:497)
	at net.minecraft.server.NetServerHandler.handleCommand(NetServerHandler.java:843)
	at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:799)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:781)
	at net.minecraft.server.Packet3Chat.handle(Packet3Chat.java:34)
	at net.minecraft.server.NetworkManager.b(NetworkManager.java:234)
	at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:119)
	at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:83)
	at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:579)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:467)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.NoClassDefFoundError: org/bukkit/command/BlockCommandSender
	at org.anjocaido.groupmanager.GroupManager.onCommand(GroupManager.java:394)
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:40)
	... 13 more
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