Verify that a zonefile hashes to the given value hash
    @zonefile_str must be the zonefile as a serialized string

def verify_zonefile( zonefile_str, value_hash ):
    """
    Verify that a zonefile hashes to the given value hash
    @zonefile_str must be the zonefile as a serialized string
    """
    zonefile_hash = get_zonefile_data_hash( zonefile_str )
    if zonefile_hash != value_hash:
        log.debug("Zonefile hash mismatch: expected %s, got %s" % (value_hash, zonefile_hash))
        return False 

    return True