But, he didn't put .com. How can they possibly deal with that anomaly?
Seriously, I've wondered what people think they are accomplishing when they write a phone number like 2five5-3seven6-2one1four on a craigslist ad. Bots are going to find it just as easily and humans can read it.
http://en.wikipedia.org/wiki/Regular_expression
also, security through obscurity is also a flawed concept to begin with. your obfuscation efforts do absolutely zilch compared to google's gmail team and their spam detection techniques.