Hi,
To protect your server you should use avast NetServer (Generated from ADNM) or if you more prefer for standalone solution you may use avast! 4 server edition.
Then to protect your clients, you can use avast NetClient (Generated from ADNM) or avast! 4 Professional edition/ avast Pro version 6.0/ avast Internet Security version 6.0 if you interest to use standalone solutions instead of managed solution.
Meanwhile for SBC (Small Business Console) according to AVAST team recommendation, only eligible for company whose implemented to coverage only 200 users maximum. If you have a planning to protect more than 200 users, we more keep prefer your corporate still using ADNM till the new version of ADNM released.
Hopefully my and WPN information could solving your confused to use avast antivirus solutions.
Cheers,