[AUCTeX] Can't load tex-site in Emacs 23 under Ubuntu Jaunty (AucTeX 11.84-0ubuntu2)

[Leo Alekseyev]

I run Emacs 23; AucTeX used to work fine for me when it was installed
via emacs-snapshot package.  Due to some problems, I reinstalled Emacs
using the Emacs 23 package (all available on
https://launchpad.net/~ubuntu-elisp/+archive/ppa).  Now AucTeX quit
working for me.  When I try to reinstall, it says "ignoring emacsen
flavor: emacs23", and tex-site doesn't load.  Copying site-lisp/auctex
from /usr/share/emacs/ to /usr/share/emacs23 doesn't help.

I'd appreciate any advice on how to get auctex working.