Withheld numbers straight to answering machine?

[LoungeLizard]

I'm one of many who has got 'Caller ID' on my landline. I have noticed that virtually all junk sales calls and competition scam calls are either:

(1) number withheld

(2) number unavailable

(3) international.

My question is: Is there any technology available which will divert all these calls straight to an answering machine or service without making the phone ring?

The beauty of this is that if any genuine callers got caught in the net then they could always leave a message; as could any sales people if they really wanted to (but they never seem to bother).

I am sure that this is technically possible because it would be no harder than assigning ring-tones to calling individuals (which my phone already does).

I already know about the telephone preference service.

[incitatus]

if you want to stop these calls, surely it is easier to pay �5 and get your number removed from the calling lists.  we never get them now.

[Kerplunk]

Register with TPS, http://www.tpsonline.org.uk/tps/ These calls will soon stop.

[becks]

If you already know about the telephone preference service why don't you just sign up to it?? Surely would be easier than sifting through messages about double glazing to see whether someone you know called you. Like the two above, we've done it and don't have a single call.

[LoungeLizard]

I am not ungrateful for the above answers but they do not answer the question I asked and are rather presumptuous.  I clearly indicated in my question that I am already aware of the Telephone Preference Service.

I repeat: I am NOT interested in systematic solutions here.  I am interested in local technical solutions.  Please, can anyone answer the question I actually asked?

[Kerplunk]

I think with a response like that you will have to rely on your own knowledge.