Getting PHP running on 10.1 is simple. 

1. su to root 
2. Edit /etc/httpd/httpd.conf 
3. Uncomment "Load Module php4_module" line. 
4. Uncomment "AddModule mod_php4.c" line. 
5. Uncomment "AddType application/x-httpd-php .php" line. 
6. Uncomment "AddType application/x-httpd-php-source .phps" line. 
7. Find "<Directory /home/*/Sites>" block and uncomment the entire Directory directive block. 

This will allow PHP to execute from ~/Sites directory.