Program: 9720
Project: 9720
Buggy source:
/** 
 * Merge classes directory and any merge jars into module jar with any specified manifest file.   META-INF directories are excluded.
 */
protected boolean assemble(Module module,File classesDir,List errors){
  if (!buildingEnabled) {
    return false;
  }
  Zip zip=new Zip();
  zip.setProject(project);
  zip.setDestFile(module.getModuleJar());
  ZipFileSet zipfileset=null;
  for (Iterator iter=module.getSrcDirs().iterator(); iter.hasNext(); ) {
    File srcDir=(File)iter.next();
    zipfileset=new ZipFileSet();
    zipfileset.setProject(project);
    zipfileset.setDir(srcDir);
    zipfileset.setIncludes(RESOURCE_PATTERN);
    zip.addZipfileset(zipfileset);
  }
  List mergeJars=module.getMerges();
  final boolean useManifest=false;
  if (0 < mergeJars.size()) {
    for (Iterator iter=mergeJars.iterator(); iter.hasNext(); ) {
      File mergeJar=(File)iter.next();
      zipfileset=new ZipFileSet();
      zipfileset.setProject(project);
      zipfileset.setSrc(mergeJar);
      zipfileset.setIncludes("String_Node_Str");
      zipfileset.setExcludes("String_Node_Str");
      zipfileset.setExcludes("String_Node_Str");
      zipfileset.setExcludes("String_Node_Str");
      zipfileset.setExcludes("String_Node_Str");
      zip.addZipfileset(zipfileset);
    }
  }
  File metaInfDir=new File(classesDir,"String_Node_Str");
  Util.deleteContents(metaInfDir);
  File manifest=new File(module.moduleDir,module.name + "String_Node_Str");
  if (Util.canReadFile(manifest)) {
    if (Util.canReadDir(metaInfDir) || metaInfDir.mkdirs()) {
      copyFile(manifest,new File(metaInfDir,"String_Node_Str"),FILTER_ON);
    }
 else {
      errors.add("String_Node_Str" + metaInfDir);
      return false;
    }
  }
  zipfileset=new ZipFileSet();
  zipfileset.setProject(project);
  zipfileset.setDir(classesDir);
  zipfileset.setIncludes("String_Node_Str");
  zip.addZipfileset(zipfileset);
  try {
    handler.log("String_Node_Str" + module + "String_Node_Str"+ module.getModuleJar());
    return executeTask(zip);
  }
 catch (  BuildException e) {
    errors.add("String_Node_Str" + module + "String_Node_Str"+ e.getMessage());
    return false;
  }
 finally {
    module.clearOutOfDate();
  }
}

Fixed version (ground truth):
/** 
 * Merge classes directory and any merge jars into module jar with any specified manifest file.   META-INF directories are excluded.
 */
protected boolean assemble(Module module,File classesDir,List errors){
  if (!buildingEnabled) {
    return false;
  }
  Zip zip=new Zip();
  setupTask(zip,"String_Node_Str");
  zip.setDestFile(module.getModuleJar());
  ZipFileSet zipfileset=null;
  for (Iterator iter=module.getSrcDirs().iterator(); iter.hasNext(); ) {
    File srcDir=(File)iter.next();
    zipfileset=new ZipFileSet();
    zipfileset.setProject(project);
    zipfileset.setDir(srcDir);
    zipfileset.setIncludes(RESOURCE_PATTERN);
    zip.addZipfileset(zipfileset);
  }
  List mergeJars=module.getMerges();
  final boolean useManifest=false;
  if (0 < mergeJars.size()) {
    for (Iterator iter=mergeJars.iterator(); iter.hasNext(); ) {
      File mergeJar=(File)iter.next();
      zipfileset=new ZipFileSet();
      zipfileset.setProject(project);
      zipfileset.setSrc(mergeJar);
      zipfileset.setIncludes("String_Node_Str");
      zipfileset.setExcludes("String_Node_Str");
      zipfileset.setExcludes("String_Node_Str");
      zipfileset.setExcludes("String_Node_Str");
      zipfileset.setExcludes("String_Node_Str");
      zip.addZipfileset(zipfileset);
    }
  }
  File metaInfDir=new File(classesDir,"String_Node_Str");
  Util.deleteContents(metaInfDir);
  File manifest=new File(module.moduleDir,module.name + "String_Node_Str");
  if (Util.canReadFile(manifest)) {
    if (Util.canReadDir(metaInfDir) || metaInfDir.mkdirs()) {
      copyFile(manifest,new File(metaInfDir,"String_Node_Str"),FILTER_ON);
    }
 else {
      errors.add("String_Node_Str" + metaInfDir);
      return false;
    }
  }
  zipfileset=new ZipFileSet();
  zipfileset.setProject(project);
  zipfileset.setDir(classesDir);
  zipfileset.setIncludes("String_Node_Str");
  zip.addZipfileset(zipfileset);
  try {
    handler.log("String_Node_Str" + module + "String_Node_Str"+ module.getModuleJar());
    return executeTask(zip);
  }
 catch (  BuildException e) {
    errors.add("String_Node_Str" + module + "String_Node_Str"+ e.getMessage());
    return false;
  }
 finally {
    module.clearOutOfDate();
  }
}