Phones Programs/Partners - Can I get miles in retrospect

I've been an MCI long distance customer for some time and never realised that one of their partners was United.

Does anyone know if I can now sign up and start to get miles credited to my United FF every month ?. The MCI website doesn't appear to say either way.

Miles for use, but not bonus miles.

However, if you call up and get denied threaten to move your service to another carrier and they may offer you miles to stay put.