Well... Since I am the one that started the thread, I guess I should give an update about my situation : system is up an running great, even tough not very fast (but I have some pages which are full of images) using the Lighttp server and PHP package.

Nevertheless, I had to increase the memory reserved for the PHP scripts to 32MB otherwise I was getting errors even on the standard Dokuwiki installation (not my wiki), on the sintax section. I edited the /etc/php.ini file.

Thanks for your work!!!