sockstat was only for freebsd, now it's on linux too. something like ‘lsof -i -n’ or ‘netstat -anpe‘.

You can get the 0.3-1ubuntu1 version at the "Builds": https://launchpad.net/ubuntu/+source/sockstat/0.3-1ubuntu1

I download it and install it on my jaunty i386 without any problem.
Intro by chihchun: http://people.debian.org.tw/~chihchun/2009/02/23/sockstat-for-linux/