The home server system is coming together, piece by piece.
Right now, the B3 has got my external HDDs plugged into it, and I am trying to access their content over the internet. This turned out to be harder than I expected.
The mounting points for the HDDs are automatically placed in the folder /home/storage/extern, but since I am using FTP to access the B3 on-line, I only get to my home folder (/home/username). No problem, just SSH into the B3 and make a link (command ln -s) to the extern folder in the home folder, right?
Wrong. In SSH the link works perfectly, but in FTP the link comes up dead. Since Mac OS X's built-in FTP client does not allow me to surf upwards in the B3's file system, I'm stuck in my home folder.
Edit 1:
Making individual links for the HDDs did not work either; these links also turn up dead in FTP. In SSH they are color-coded as "access not authorized".
Edit 2:
Hacking the FTP client a bit, I found that by connecting to <servername>.myownb3.com/../../storage/extern/, I get direct access to the extern folder, but that's the end of the fun stuff, because when I open the subfolders representing each HDD, no content is shown.
Edit 3:
I'm starting to answer my own posts, aint I?

It turns out that the 'no content shown' was due to the fact that the computer takes a looong time to load the file list for each HDD. I did not notice this, since the status bar in Finder windows is turned off by default in Lion.
Now I have access! Yay is me!
Instead, I have another question: does anyone out there know how to make a Mac load these disks automatically and mount them on the desktop? (I will post such a question in an ordinary Mac forum as well.)
What to do?
All suggestions are greatly welcomed,
Anders