The Ubuntu guys merged Debian experimental PHP 5.3.3 into bzr for Ubuntu 10.10 Maverick.
https://launchpad.net/ubuntu/maverick/+source/php5
I changed the release tag to Lucid and disabled running mysqld for testing (which seems to be new, not sure why it doesn't work on Lucid atm) and uploaded to my Launchpad PPA. It compiles, with various warnings, and php-fpm runs on my testing server without problems.
They broke out the fpm pool definitions into a separate conf.d folder. Not a bad idea.
Here's the repo if anyone wants to play with it. Not recommended for production use.
https://launchpad.net/~brianmercer/+archive/testing