windows 2003 SBS server licensing with vpn

My company has 9 workstations and would like to setup a domain controller running windows 2003 SBS server. The 9 workstations would connect to the domain controller and we would also have two computers connect through VPN access. My question is does Windows 2003 SBS server allow VPN connections and would I have to purchase additional CALs to connect all the workstations? If I do have to purchase additional CALs would I have to purchase CALs for the two computers that connect via VPN? Thanks in advance for any help