First step, install the libnss3-tools:
sudo apt-get install libnss3-tools
There is a mention on that page linked above that says the cert needs to be imported as a CA due to a bug. On Natty Ubuntu it was not necessary. I put the following function in my .bashrc
function trustCert() {
[ $# -ne 2 ] && echo "you need to provide [certificate_nickname] and [certificate_filename]" && return 1
certutil -d sql:$HOME/.pki/nssdb -A -t "P,," -n $1 -i $2
}