Manual Update for Server in closed network

I am working with somebody who wants Avast on their PCs and Servers on a closed network. They have no internet access. But, sometimes people bring USB drives or CDs and thus the network needs to have AV.

How do they keep Avast up to date?
Where can they download the latest updates?
How do they install these updates?

It seems that there is a download for Avast Pro for the XP PCs and this can be put on a memory stick and brought in to the network. But, is there something similar for the Server?

Thanks in advance,
JC

Will this answer?
http://forum.avast.com/index.php?topic=36738.msg307930#msg307930

I hope so this will work.

The link http://www.avast.com/eng/update_avast_4_vps.html is where the .exe can be downloaded. This is for Windows. It seems that this downloaded files can be used to update both Pro and Server on Windows machines. The program update seems to need the latest download of the program from here: http://www.avast.com/eng/programs.html

I hope this works. Has anybody successfully done updates this way?

Thanks,
JC