Rhq-apache-bmx is a project mainly written in Java, it's free.
Experimental monitoring plugin for RHQ to monitor apache httpd with the help of mod_bmx
Simple proof of concept plugin to monitor apache httpd via mod_bmx. You can find mod_bmx at https://github.com/hyperic/mod_bmx Install notes for mod_bmx are here: https://github.com/hyperic/mod_bmx/blob/master/INSTALL.txt
The plugin by default assumes the bmx handler to be at /bmx and not to be protected