com Zombies

[19:30:11] [Server thread/INFO]: MrMinemeet20 issued server command: /zombies createarena Nuketown
[19:30:11] [Server thread/ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'zombies' in plugin COM_Zombies v1.2.6
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:181) ~[craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at org.bukkit.craftbukkit.v1_8_R1.CraftServer.dispatchCommand(CraftServer.java:643) ~[craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at net.minecraft.server.v1_8_R1.PlayerConnection.handleCommand(PlayerConnection.java:1083) [craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at net.minecraft.server.v1_8_R1.PlayerConnection.a(PlayerConnection.java:918) [craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at net.minecraft.server.v1_8_R1.PacketPlayInChat.a(PacketPlayInChat.java:26) [craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at net.minecraft.server.v1_8_R1.PacketPlayInChat.a(PacketPlayInChat.java:53) [craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at net.minecraft.server.v1_8_R1.PacketHandleTask.run(SourceFile:13) [craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.7.0_71]
	at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.7.0_71]
	at net.minecraft.server.v1_8_R1.MinecraftServer.z(MinecraftServer.java:686) [craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at net.minecraft.server.v1_8_R1.DedicatedServer.z(DedicatedServer.java:316) [craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at net.minecraft.server.v1_8_R1.MinecraftServer.y(MinecraftServer.java:627) [craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at net.minecraft.server.v1_8_R1.MinecraftServer.run(MinecraftServer.java:530) [craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at java.lang.Thread.run(Unknown Source) [?:1.7.0_71]
Caused by: java.lang.NoClassDefFoundError: net/minecraft/server/v1_8_R3/Packet
	at com.zombies.commands.CreateArenaCommand.onCommand(CreateArenaCommand.java:36) ~[?:?]
	at com.zombies.commands.ZombiesCommand.onCommand(ZombiesCommand.java:228) ~[?:?]
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	... 14 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_8_R3.Packet
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:91) ~[craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.7.0_71]
	at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.7.0_71]
	at com.zombies.commands.CreateArenaCommand.onCommand(CreateArenaCommand.java:36) ~[?:?]
	at com.zombies.commands.ZombiesCommand.onCommand(ZombiesCommand.java:228) ~[?:?]
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[craftbukkit.jar:git-Spigot-da32fe1-df0b4c1]
	... 14 more