Can't change zombies speed/damage

Hello, I am new to plugin developing. I am trying to make a plugin to change the speed and damage of zombies. I have followed this post: http://forums.bukkit.org/threads/best-way-of-changing-mobs-move-speed.65378/#post-1118928

Here's my main class:
http://pastie.org/4196152

Here's the error I am getting:

Code:

20:35:23 [GRAVE] Could not load 'plugins/FastZombie.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.ClassCastException: class me.Hound.FastZombie.FastZombie
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:151)
    at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:305)
    at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:230)
    at org.bukkit.craftbukkit.CraftServer.loadPlugins(CraftServer.java:213)
    at org.bukkit.craftbukkit.CraftServer.<init>(CraftServer.java:189)
    at net.minecraft.server.ServerConfigurationManager.<init>(ServerConfigurationManager.java:53)
    at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:166)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:432)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.ClassCastException: class me.Hound.FastZombie.FastZombie
    at java.lang.Class.asSubclass(Class.java:3018)
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:141)
    ... 8 more

So, am I doing anything wrong? Sorry if my mistake is dumb, I'm new to Bukkit/Java programming.

 

You need your plugins main class to extend JavaPlugin