Really interested to know who really controls the do not call list for cell phones and does it really works against unwanted marketing calls. I used to get a lot of marketing calls during my office hours. I am using sprint mobile service in Wichita (Kansas). I have no option to tackle such unwanted calls and i am seriously looking for a service to stop them. Any one has got any suggestion about it or any other service that i can really use to prevent the unwanted marketing calls.