Same complaint as others, several calls a day, no voicemails left and if I call back to the number I get the vm that the extension is unavailable.  I don't use my home line much and so I hadn't noticed it until the phone rang when I was actually home and I saw all the missed calls.  I just filed a complaint on the do not call reg site.  Some of the calls the caller ID says "unknown" and some it says "preferred guest."