Nothing is impossible (Score 1)

The spam problem has a technical solution. The keyword is innovation. The programs that recognize CAPTCHAs could be defeated for example by using evolutionary CAPTCHA described here http://network-security-research.blogspot.com/2008/08/around-captcha.html Malicious human CAPTCHAs recognitions could be defeated as well. And perhaps such approaches will appear in a short period of time ;-)