At Onoko, I’ve been using Quercus to run PHP applications on Elastic Beanstalk, Amazon’s scalable Java stack.
Quercus is great, although I’ve found I have to work round some of its unimplemented methods or implementation differences from PHP. I test on a plain Linux/Apache/PHP server though, and wanted a way to detect Quercus so I can conditionally use different work arounds. You can do this with the following PHP:
$IS_QUERCUS = strpos($_SERVER[“SERVER_SOFTWARE”],’Quercus’) !== false;