Exception in thread "Server console handler" java.lang.NoClassDefFoundError: net
/minecraft/command/ServerCommand
        at net.minecraft.server.dedicated.DedicatedServer.func_71331_a(Dedicated
Server.java:363)
        at net.minecraft.server.dedicated.DedicatedServer$2.run(DedicatedServer.
java:99)
Caused by: java.lang.ClassNotFoundException: net.minecraft.command.ServerCommand

        at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLo
ader.java:188)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        ... 2 more
Caused by: java.lang.OutOfMemoryError: PermGen space