OpenBSD's apache comes chrooted by default since obsd3.2.
While it is slighly more complicated, it is possible to serve dynamic content from a chroot...
Many people have php & postgresql/mysql serving from a chroot apache. All (*) you need is your php binaries inside your chroot as well as perhaps /etc/hosts to resolve localhost or what ever hostname you need, and connect to your database through sockets instead of named pipes...

(Ok, I admit I haven't bothered to try it myself, but it is doable)

Ammo