Program: 18931
Project: 18931
Buggy source:
public void onEnable(){
  checkForLibs();
  trans=new Translation();
  instance=this;
  log=getServer().getLogger();
  try {
    dclistener=new DropChestListener();
  }
 catch (  NoClassDefFoundError e) {
    dclistener=null;
  }
  try {
    worldguard=(WorldGuardPlugin)getServer().getPluginManager().getPlugin("String_Node_Str");
  }
 catch (  Exception e) {
    worldguard=null;
  }
  PluginDescriptionFile pdfFile=this.getDescription();
  PluginManager pm=getServer().getPluginManager();
  pm.registerEvent(Type.PLAYER_INTERACT,playerListener,Priority.Normal,this);
  pm.registerEvent(Type.PLAYER_PICKUP_ITEM,playerListener,Priority.Low,this);
  pm.registerEvent(Type.BLOCK_BREAK,blockListener,Priority.Low,this);
  pm.registerEvent(Type.PLAYER_DROP_ITEM,playerListener,Priority.Normal,this);
  pm.registerEvent(Type.CHUNK_LOAD,worldListener,Priority.Normal,this);
  pm.registerEvent(Type.CHUNK_UNLOAD,worldListener,Priority.Normal,this);
  pm.registerEvent(Type.BLOCK_PHYSICS,blockListener,Priority.Normal,this);
  if (dclistener != null) {
    pm.registerEvent(Type.CUSTOM_EVENT,dclistener,Priority.Normal,this);
  }
  for (  World w : getServer().getWorlds()) {
    for (    Entity e : w.getEntities()) {
      if (e instanceof Item) {
        Location loc=e.getLocation();
        Block b=loc.getBlock();
        if (b.getType().equals(Material.GLASS) || b.getType().equals(Material.STEP)) {
          e.remove();
        }
      }
    }
  }
  load();
  config=new Configuration();
  if (pm.getPlugin("String_Node_Str") != null) {
    config.setUseSpout(true);
  }
  if (config.useSpout()) {
    if (!NarrowtuxLib.getInstance().installSpout()) {
      config.setUseSpout(false);
    }
  }
  odditem=(OddItem)pm.getPlugin("String_Node_Str");
  trans.reload(new File(getDataFolder(),"String_Node_Str" + config.getLocale() + "String_Node_Str"));
  if (trans.getVersion() < 5) {
    try {
      copyFromJarToDisk("String_Node_Str" + config.getLocale() + "String_Node_Str",getDataFolder());
      log.log(Level.INFO,"String_Node_Str" + config.getLocale() + "String_Node_Str");
      trans.reload(new File(getDataFolder(),"String_Node_Str" + config.getLocale() + "String_Node_Str"));
    }
 catch (    IOException e) {
      System.out.println("String_Node_Str");
    }
  }
  playerListener.config=config;
  registerProvider(new BasicShowcase());
  registerProvider(new FiniteShowcase());
  registerProvider(new InfiniteShowcase());
  registerProvider(new ExchangeShowcase());
  registerProvider(new TutorialShowcase());
  getServer().getScheduler().scheduleSyncDelayedTask(this,new ItemSpawner(),20);
  getServer().getScheduler().scheduleSyncRepeatingTask(this,watcher,10,40);
  setupPermissions();
  if (config.getAutosaveInterval() != -1) {
    getServer().getScheduler().scheduleSyncRepeatingTask(this,new Runnable(){
      public void run(){
        save();
        if (config.isShowingAutosaveNotification()) {
          log.log(Level.INFO,"String_Node_Str");
        }
      }
    }
,0,config.getAutosaveInterval() * 20);
  }
  String logText=trans.tr("String_Node_Str",pdfFile.getName(),pdfFile.getVersion());
  log.log(Level.INFO,logText);
}

Fixed version (ground truth):
public void onEnable(){
  checkForLibs();
  trans=new Translation();
  instance=this;
  log=getServer().getLogger();
  try {
    dclistener=new DropChestListener();
  }
 catch (  NoClassDefFoundError e) {
    dclistener=null;
  }
  try {
    worldguard=(WorldGuardPlugin)getServer().getPluginManager().getPlugin("String_Node_Str");
  }
 catch (  Exception e) {
    worldguard=null;
  }
  PluginDescriptionFile pdfFile=this.getDescription();
  PluginManager pm=getServer().getPluginManager();
  pm.registerEvent(Type.PLAYER_INTERACT,playerListener,Priority.Normal,this);
  pm.registerEvent(Type.PLAYER_PICKUP_ITEM,playerListener,Priority.Low,this);
  pm.registerEvent(Type.BLOCK_BREAK,blockListener,Priority.Low,this);
  pm.registerEvent(Type.PLAYER_DROP_ITEM,playerListener,Priority.Normal,this);
  pm.registerEvent(Type.CHUNK_LOAD,worldListener,Priority.Normal,this);
  pm.registerEvent(Type.CHUNK_UNLOAD,worldListener,Priority.Normal,this);
  pm.registerEvent(Type.BLOCK_PLACE,blockListener,Priority.Normal,this);
  if (dclistener != null) {
    pm.registerEvent(Type.CUSTOM_EVENT,dclistener,Priority.Normal,this);
  }
  for (  World w : getServer().getWorlds()) {
    for (    Entity e : w.getEntities()) {
      if (e instanceof Item) {
        Location loc=e.getLocation();
        Block b=loc.getBlock();
        if (b.getType().equals(Material.GLASS) || b.getType().equals(Material.STEP)) {
          e.remove();
        }
      }
    }
  }
  load();
  config=new Configuration();
  if (pm.getPlugin("String_Node_Str") != null) {
    config.setUseSpout(true);
  }
  if (config.useSpout()) {
    if (!NarrowtuxLib.getInstance().installSpout()) {
      config.setUseSpout(false);
    }
  }
  odditem=(OddItem)pm.getPlugin("String_Node_Str");
  trans.reload(new File(getDataFolder(),"String_Node_Str" + config.getLocale() + "String_Node_Str"));
  if (trans.getVersion() < 5) {
    try {
      copyFromJarToDisk("String_Node_Str" + config.getLocale() + "String_Node_Str",getDataFolder());
      log.log(Level.INFO,"String_Node_Str" + config.getLocale() + "String_Node_Str");
      trans.reload(new File(getDataFolder(),"String_Node_Str" + config.getLocale() + "String_Node_Str"));
    }
 catch (    IOException e) {
      System.out.println("String_Node_Str");
    }
  }
  playerListener.config=config;
  registerProvider(new BasicShowcase());
  registerProvider(new FiniteShowcase());
  registerProvider(new InfiniteShowcase());
  registerProvider(new ExchangeShowcase());
  registerProvider(new TutorialShowcase());
  getServer().getScheduler().scheduleSyncDelayedTask(this,new ItemSpawner(),20);
  getServer().getScheduler().scheduleSyncRepeatingTask(this,watcher,10,40);
  setupPermissions();
  if (config.getAutosaveInterval() != -1) {
    getServer().getScheduler().scheduleSyncRepeatingTask(this,new Runnable(){
      public void run(){
        save();
        if (config.isShowingAutosaveNotification()) {
          log.log(Level.INFO,"String_Node_Str");
        }
      }
    }
,0,config.getAutosaveInterval() * 20);
  }
  String logText=trans.tr("String_Node_Str",pdfFile.getName(),pdfFile.getVersion());
  log.log(Level.INFO,logText);
}