It was grounds for me getting 2 things: 1. A caller ID box that can recognize certain numbers and play them a discouraging message, and 2. An answering machine without a tape so I can immediately delete unwanted stuff. When playing back -- it shows who called with the message -- delete can come really quick.
I may have to go to an answering machine. I have voice mail now, and it won't let me delete them until their 5 minute speech is finished, but then, my phone company is the absolute worst!