There are only TWO types of CALs that you can purchase - USER or DEVICE. I'd suspect that if you are running out of CALs that you most likely have and want USER CALs (which are the more popular type -- DEVICE CALs are generally only used for companies that have shift workers who share a computer).
You'll find the overview of SBS pricing here:
http://www.microsoft.com/windowsserver2003/sbs/howtobuy/pricing.mspx
(note that even though all CALs are now labeled "R2" these are still valid for non-R2 servers).
So, assuming that you are buying RETAIL USER CALs the SKU you want to make sure you get for the 5-pack is T74-00002. If you are buying under the Open Value License program, then you want SKU T74-00192.
I'll guess, though, that you aren't buying under the licensing program because if you were you'd be contacting your licensing specialist rather than searching on the web.
So, just search for "T74-00002" and you'll find what you need. (I see a low price of around $329.00 or from somewhere like NewEgg for about $345.00 for the 5-pack).
Microsoft Licensing info:
http://www.microsoft.com/windowsserver2003/sbs/howtobuy/licensing.mspx (again, remember even though it says "R2" it applies for non-R2 servers)
Jeffrey B. Kane
Microsoft Small Business Specialist - Licensing Specialist
TechSoEasy
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