Collection Agency saying "hang up if you're not so-and-so"

[hnhlvr]

Question: Is the following a violation of law?

I never pick up collection calls and recently on my voice mail, I've received two calls where the person will say "if this isn't [my name] then hang up now because the matter I'm about to discuss is a private one. By not hanging you, you acknowledge you are this person and that this matter can be discussed." Then the person goes on to talk about how they're out to collect a debt. It's a real person, not an automated machine.

If they do have the wrong number and leave that message, wouldn't the person who's voice mail that went to be compelled to listen to the message and find out that debt collectors are after me?

Thoughts?

[BigJohn]

Next time they call, listen to them and object to paying. When they are almost finished, ask them "Who was it you wanted to speak to?"