Okie dokie, I'll step in.
It's really easy. All you're going to do is exactly what he posted. Go into terminal. I'm positive you know where that is.
Once there, simply type:
sudo apt-get install mediatomb
Once done, do into your computer and in the etc/mediatomb folder is the file CONFIG.XML (edit this)
On line 23 (LOOK FOR IT IN THE FILE)
It will have the <protocolInfo extend="no"/> CHANGE THAT TO yes and SAVE
Now, in terminal again, type:
sudo /etc/init.d/mediatomb restart
When it loads up, just edit what you want to add to the server and you're golden.
Another option, if you really want to play around, is to put linux on your PS3. I'm running a partition of Yellow Dog Linux along with the PS3-2.41 Firmware. It allows me to do whatever I want on it (torrent, movies, music, media connection to Mint in the other room, etc) and I can just double-click the PS3 icon and bounce over to the game system.
Carry on, my friend!