title: NoSuchMethodError even though self-coded method exists
body: <p>I've been searching for a solution for my problem but haven't got any sufficient answers.</p>
  
  <p>I am working on a <a href="http://bukkit.org/" rel="nofollow">Bukkit</a> plugin's update system. Thus, I had to code the classes myself. But all the time I'd like to call a method (to be specific: <a href="https://github.com/lirtistasya/RegionManager/blob/master/src/com/lirtistasya/bukkit/util/BukkitPlugin.java#L81" rel="nofollow">debug(String)</a>) as a wrapped method from <a href="https://github.com/lirtistasya/RegionManager/blob/master/src/com/lirtistasya/bukkit/util/net/Updater.java#L277" rel="nofollow">another class</a>, I get the following <code>NoSuchMethodError</code>:</p>
  
  <pre><code>[RegionManager] Enabling RegionManager v1.0.0
  [RegionManager] [DEBUG] loading configuration options...
  [RegionManager] [DEBUG] done.
  [RegionManager] [DEBUG] initializing attributes...
  [RegionManager] [DEBUG] done.
  [RegionManager] [DEBUG] registering commands and events...
  [RegionManager] [DEBUG] done.
  [RegionManager] [DEBUG] fetching WorldGuard...
  [RegionManager] [DEBUG] done.
  [RegionManager] [DEBUG] checking for updates...
  [SEVERE] Exception in thread "update/version check" 
  [SEVERE] java.lang.NoSuchMethodError: com.lirtistasya.bukkit.util.BukkitPlugin.debug(Ljava/lang/String;)V
  [SEVERE]    at com.lirtistasya.bukkit.util.net.Updater.debug(Updater.java:278)
  [SEVERE]    at com.lirtistasya.bukkit.util.net.Updater.access$0(Updater.java:277)
  [SEVERE]    at com.lirtistasya.bukkit.util.net.Updater$UpdateRunnable.run(Updater.java:284)
  [SEVERE]    at java.lang.Thread.run(Unknown Source)
  </code></pre>
  
  <p>It would be great if anyone could help me with this...</p>