Buy the mod_perl book - it explains in depth how to make mod_perl provide extensions to httpd.conf syntax which sounds exactly what you want!

The book's home is here

http://www.modperl.com/

And it is called Writing Apache Modules with Perl and C

PS Thoughtfully the author has put the relevant chapter online <a href=http://www.modperl.com/book/chapters/ch8.html">here ;-)