Currently the server integration infrastructure is tailored for Java EE (or Java Web) servers, and can not be easily used for technologies that are not based on the Java EE standards, such as PHP, Ruby on Rails and others. In particular, the user interface that allows registering servers in the Services tab can only be used for Java EE servers, and non-Java EE servers (e.g. Apache) can not use this UI. The desire is to be able to use some parts of the server integration infrastructure (including the Servers node) by non-Java EE servers which are used in non-Java technologies.
Wiki page: http://wiki.netbeans.org/wiki/view/CommonServerAPI
The code is located under serverplugins/server in cvs trunk (not in build).
Thanks for your comments. I will integrate the spi into the build tomorrow.
Integrated into the trunk.