How to extend the LanguageManager class in a plugin

ExampleExtension.java

//This is skeleton/prototype code, just to explain how setting a custom LanguageManager would work
import net.glowstone.util.lang.LanguageManager;

class MyLanguage extends LanguageManager() {
  /*
  Methods and etc for the class, however you want it to work.
  */
}
/*
 * Now to the plugin
 */
import net.glowstone.GlowServer;
import io.gist.MyLanguage;

class MyPlugin extends /* or implements, idk, skeleton code */ Plugin {
  public void onStart() {
   ((GlowServer) Bukkit.getServer()).setLanguageManager(new MyLanguage()); //Sets the custom language manager
  }
}