I met this problem today morning after I started the sshd service. I think it is because I just updated my Fedora recently, and the ssh known_hosts file in your home directory should be updated too. There are 3 solutions to solve this,
http://www.cyberciti.biz/faq/warning-remote-host-identification-has-changed-error-and-solution/

The simple solutions to this problem are:
$ cd
$ rm .ssh/known_hosts
$ ssh ras.mydomain.com
or just:
ssh-keygen -R server.example.com

Fedora 14 was released before I remembered that I should update my Fedora 12 to 13. So I was lucky to install Fedora 14 directly instead of 13. I tried the live CD and the installation was fast and pleasant, less than 5 mins. Later on, I found out it was very painful to use live CD as the installation media. Lots lots of packages are not there. So I spend hours in the afternoon to install the packages I need. Today when I planned to do some programming, and found out that GCC is not installed?? What the hell? Linux without GCC? Fortunately, you can use yum to install all these packages very easy, like:

yum groupinstall “Development Tools” “Development Libraries”

yum groupinstall “GNOME Software Development” “X Software Development” “Java Development” “Legacy Software Development” “KDE Software Development” “Fedora Packager” “XFCE Software Development” “Web Development”