Well I was hoping that by exposing the parsed memcache connection info as parameters it would be just a matter of using those parameters in doctrine cache config so I did not include this code yet. However it turned out to be very hard to do it this way to I've added a factory for this + some example config on how to use it:
https://github.com/janus-ssp/janus/commit/fb3f0f546ef39f4eac514b7513cc15a1084fbd0e