As some of you might have noticed, I've been a bit busy lately creating new PECL extension - sphinx.
The extension provides an interface to a feature-rich fulltext search engine Sphinx written by Andrew Aksyonoff.
We (Andrew and me) made our best to keep the extension as compatible to the pure-PHP API (shipped with Sphinx) as possible in order to make the transition easier, so if you're already using PHP API, you only need to remove (or comment out) the include "sphinxapi.php"; line and enable the extension in your php.ini.
Yes, it's that easy.

I also added a documentation for it to the PHP manual - http://php.net/sphinx, it covers all the functions, but lacks code examples at the moment (contact me if you want to contribute some, it's very much appreciated).

To install the extension you need libsphinxclient (it's shipped with Sphinx since v0.9.8), here is a short installation guide:

# tar -xzvf sphinx-0.9.8.tar.gz
# cd sphinx-0.9.8/api/libsphinxclient/
# ./buildconf.sh
# ./configure && make install

After that PECL will do all the work for you:

# pecl install sphinx-beta

I've got no complaints so far, so I suppose I can call it stable in a month or so.
Until then I'll continue to gather feedback (please use PECL bug-tracker if you encounter any problems, thanks!).