Avast 4 SBS licensing

Why do I have to order minimum 5 licenses if I only need antivirus for SBS server?
what are those 5 licenses? Does that mean I get Avast 4 SBS for 5 SBS servers?

Currently we have SBS 2003 and 6 workstations what solution do I choose If I want protection for all computers in the offise? SBS Suite with quantity 6 or 7?
And if I decide only to protect SBS 2003 server with avast product and choose competitors solutions for workstations, what avast product should I choose so I don’t have to pay for more then 1 license for server itself?

just like SBS itself
the SBS suite is a all-in-one package for SBS

u buy the package to run it on the SBS suite and u get several client licenses with it…

so its not 5 sbs server protected, its 1 server protected (if u need to run 2 sbs servers then u better be looking to setup the network propperly) and the rest for client protection