OS & DB licencing requirements

Rhythmyx Technical Discussion
1

What is the minimum number of licences & CALs I need to purchase to run Rhythmyx 5.x or 6.x with 20 end users ?

1 x W2K3 Std
+
1 x W2K3 CAL
+
1 x SQL Server 2005 Std
+
1 x SQL Server 2005 CAL

?