I am planning to setup a new business. I want to give long distance through IP phones to my potential customers. So far I came up with getting a billing solution a softswitch and IP phones. My question is, is there a way in the world that I can integrate IP phones with VOICE mail, something like, I am not home please leave a message. Are there IP phones with built in voice mail. I am looking for the simplest most basic and most affordable solution if there is one.