jrg_uk

This message is just from Trend Micro's Interscan Web Security Suite product (that's the "IWSS" bit. It's typically hooked into existing web proxies via ICAP.)

Trend have an "interesting" track-record of site categorisation, but it's possible that the URL is correctly categorised and the operators of the IWSS have chosen to block that category.

Then again, the people that Trend employ to visit websites probably just saw the name "Hacker news" and filed it as 'hacking'/bad stuff. They probably don't spend too much time on any individual web site.