How to start persistent connection with Libmemcached

Maybe they can be passed in the 'options' of the frontend:

There used the PHP \Memcached but miss the persistent_id in the __construct function.

So I tested in 1.3.4 and no way to use the persistent connection with libmemcached in Phalcon.

And, can you fix it in 1.3.5 maybe?

The option 'persistent', it doesn't work in 2.0.9.Did fix this problem?