In a new post today, Alexey Zakhlestin talks about "limited implementation" of the SCGI protocol that he created in PHP.
I finally found some time (and inspiration) to do something in direction of implementing FastCGI the way I see it. Initially, I was going to implement FastCGI-functions in php-extension, but that would require more time than I currently have, so I started with a simplier task: I implemented SCGI protocol (which is way simplier than FastCGI) in pure php-code (which is easier, again, and let's me change API faster, during development).
The result is this project (hosted on the Google Code site) that allows you to use it with any SCGI-enabled server (apache and lighttpd. He includes a source code example to clarify its use.