def jarSources(target, source, env, for_signature):
    """Only include sources that are not a manifest file."""
    try:
        env['JARCHDIR']
    except KeyError:
        jarchdir_set = False
    else:
        jarchdir_set = True
        jarchdir = env.subst('$JARCHDIR', target=target, source=source)
        if jarchdir:
            jarchdir = env.fs.Dir(jarchdir)
    result = []
    for src in source:
        contents = src.get_text_contents()
        if contents[:16] != "Manifest-Version":
            if jarchdir_set:
                _chdir = jarchdir
            else:
                try:
                    _chdir = src.attributes.java_classdir
                except AttributeError:
                    _chdir = None
            if _chdir:
                # If we are changing the dir with -C, then sources should
                # be relative to that directory.
                src = SCons.Subst.Literal(src.get_path(_chdir))
                result.append('-C')
                result.append(_chdir)
            result.append(src)
    return result
Only include sources that are not a manifest file.