SBS Premium CAL Licence question

We have a client looking to upgrade from SBS 2003 to SBS Server 2008 – which they have already bought and have the licence for

They have 18 users in total

They want the SBS 2008 Premium option so they can install the 2nd server and SQL server

All 18 users will use the SQL server

The question is: How many SBS Server 2008 standard CALs do they need? Or do they just need 18 SBS 2008 Premium CALs?

Any help on this would be gratefully received

I think that your SBS CALs only allow access to components equal to the version that matches the product. If you have a Windows Server 2008 in the SBS 2003 R2 domain, your SBS 2003 R2 CALs are applicable until May 31, 2009, after which you will be required to either have Windows Server 2008 CALs or SBS 2008 CALs to be in compliance with your license.