Exaile finds the wrong 'local' cover

I have 3 cover jpgs in each directory (album):
  cover.jpg
  coverSmall.jpg
  coverLarge.jpg

Now exaile always find 'coverSmall.jpg'.
What I would like is:

1. search for covers with the name: 'album.[jpg|png|gif]' or 'cover.[jpg|png|gif]' or 'front.[jpg|png|gif]'
2. If (1) didn't give a cover then search for files which end in 'jpg|png|gif'

So I changed "./xl/cover.py" into:

       """
            Sets up the cover search method
        """
        CoverSearchMethod.__init__(self)
        self.preferred_names = ['album.jpg', 'cover.jpg', 'front.jpg',
                                'album.png', 'cover.png', 'front.png',
                                'album.gif', 'cover.gif', 'front.gif']
        self.exts = ['.jpg', '.jpeg', '.png', '.gif']

    def find_covers(self, track, limit=-1):
        covers = []
        try:
            search_dir = os.path.dirname(track.local_file_name())
        except AttributeError:
            raise NoCoverFoundException()

        if not os.path.isdir(search_dir):
            raise NoCoverFoundException()
        for file in os.listdir(search_dir):
            if not os.path.isfile(os.path.join(search_dir, file)):
                continue

            # check preferred names
            if file.lower() in self.preferred_names:
                covers.append(os.path.join(search_dir, file))
                if limit != -1 and len(covers) == limit:
                    return covers

        for file in os.listdir(search_dir):
            if not os.path.isfile(os.path.join(search_dir, file)):
                continue

            # check for other names
            (pathinfo, ext) = os.path.splitext(file)
            if ext.lower() in self.exts:
                covers.append(os.path.join(search_dir, file))
                if limit != -1 and len(covers) == limit:
                    return covers