def update_archive(self, archive):
        self.__super_update_archive(archive)
        # only do this if the gzip module was imported globally, and
        # gzip'ing was enabled via mm_cfg.GZIP_ARCHIVE_TXT_FILES.  See
        # above.
        if gzip:
            archz = None
            archt = None
            txtfile = os.path.join(self.basedir, '%s.txt' % archive)
            gzipfile = os.path.join(self.basedir, '%s.txt.gz' % archive)
            oldgzip = os.path.join(self.basedir, '%s.old.txt.gz' % archive)
            try:
                # open the plain text file
                archt = open(txtfile)
            except IOError:
                return
            try:
                os.rename(gzipfile, oldgzip)
                archz = gzip.open(oldgzip)
            except (IOError, RuntimeError, os.error):
                pass
            try:
                ou = os.umask(2)
                newz = gzip.open(gzipfile, 'w')
            finally:
                # XXX why is this a finally?
                os.umask(ou)
            if archz:
                newz.write(archz.read())
                archz.close()
                os.unlink(oldgzip)
            # XXX do we really need all this in a try/except?
            try:
                newz.write(archt.read())
                newz.close()
                archt.close()
            except IOError:
                pass
            os.unlink(txtfile)