I finally got around to getting LJUpdate working. I hadn't felt the need with various other clients, but with a new job it's the most appropriate method for ease of posting from work.
The biggest hurdle has been finding a tarball for the http-emacs elisp files, specifically because it is only currently available via CSV. So after grabbing copies from there I made my own tarball and dumped it here
. It only needs to be extracted in the relevant site-lisp/ or elisp/ directory for your system.
Since that project appears to have been abandoned, being unmodified since 2004, I don't see any harm in providing it separately from the project page. For the non-*nix users, there's also a zipped copy