Absolutely!

Of course, an antivirus is useful only if it is being updated on a regular basis (at least the virus database). We provide a form of updates designed particularly for offline users -- updates via the vpsupd.exe program.
The vpsupd.exe program has about 1MB and contains the latest virus database. To apply the update to an offline computer, download the vpdupd.exe file (on a different machine, of course

), put it on a disk and execute it on the offline target. The program should automatically detect installed avast and do all stuff needed to make it up-to-date. You should do this at least once a week (we issue virus database updates at least twice a week, at the moment).
The vpsupd.exe program can be found here:
http://www.avast.com/iavs4pro/vpsupd.exe .
Hope this helps,
Vlk