I'm a Tor newbie. I've installed tor and tor-browser on Ubuntu 12.04 machine. It launches well and seems to work as expected. I wanted to set my exit node in the country of my choosing and found the ExitNodes directive followed by {us} should do it. So I added ExitNodes {us} to the very end of my /etc/tor/torrc and did a sudo service tor restart. I restarted the tor-browser but when navigating to https://dnsleaktest.com/, it still tells me I'm somewhere else (in Switzerland). Why is this and how do I use the ExitNodes correctly?
EDIT 1
The repo I got my instance from is deb-src http://deb.torproject.org/torproject.org precise main