This page might be helpfull.
It explains how to configure Apache2. This page is still a work in progress but I hope it helps you.
The easiest configuration is to use mod_proxy.
Have the Jetty process listen on a high, local port (say, 127.0.0.1:9090) and have an Apache virtualhost definition that proxies relevant requests to the server. The following fragment shows a VirtualHost configuration fragment that proxies for both the application interface and the webservices interface.
ProxyPass /xas http://127.0.0.1:9090/xas ProxyPassReverse /xas http://127.0.0.1:9090/xas ProxyPass /ws http://127.0.0.1:9090/ws ProxyPassReverse /ws http://127.0.0.1:9090/ws