Here's somethings that I think helped:
- Initially just used Ubuntu gems to install rails. When I tried to start the server it complained it needed a newer rubygems (gem).
- Install new rubygems from the website. Hopefully a future Ubuntu upgrade to rubygems won't wipe this out.
- Default page that shows server configuration had an error complaining about missing sqlite3 file.
- I don't know if the sqlite3-ruby gem was installed already or not, but I think it may have been.
- sudo aptitude install libsqlite3-dev libsqlite3-ruby helped, but I don't know which did it.
I did other things too, but I'm not sure which are were necessary. I guess I'll get to find out when I install on the Fedora ami :-)