How long ago did you register it? IIRC, it only lasts 3 years and you have to re-register it. If it's been more recent then you need to invetigate it and ask the telemarketers where they got your # from. I believe it's illegal for them to have it and you may be able to threaten lawsuit if the calls keep coming from the same places.
its a lot of those recorded messages "We have an importnat call for you but all operators are currently busy, please stay on the line etc."
