Apache port included dso modules

[fbsd]

In the hpptd.conf file their are a bunch of DSO modules being
included.

Are these required by Apache to run?

The only one I know for sure I am using is the PHP4 one.

Can I comment the rest out to disable them as I considerer
anything I am not really using as possible security leaks?

Is there documentation on what these DSO modules do and how to use
them?