A few words of thanks would be greatly appreciated.

Installing Opera 10 under Ubuntu 9.04 (Jaunty)

If you already have an older version of Opera, first remove it: sudo apt-get remove opera
(This operation will not results in the lost of your configuration or your bookmarks.)

Then do:

sudo wget -O - http://deb.opera.com/archive.key | sudo apt-key add -
sudo bash -c 'echo "deb http://deb.opera.com/opera/ sid non-free " > /etc/apt/sources.list.d/opera.list'
sudo apt-get update
sudo apt-get install opera