[i]1/. Is it possible to transfer the additional CAL'S if we were to purchase another copy of SBS 2003[/i]
No it is not permissible as CAL's are tied to the Original Hardware that they where first used on. Even then if you switch to a different Version of Server 2003 they also have different CAL's to go with that version.
[i]2/. If we were to retain our current server with the software on as a backup, is it possible to purchase a second server license and run both servers woith the same 15 additional CAL'S as we would only be accessing one server at any time.[/i]
No it is not permissible to use the Existing CAL's on a different version of the OS. see above for the technical reasons.
If you want to look at the Legal Reasons this is because M$ consider this a form of Piracy and will hit the Business with a $250,000.00 Fine for Piracy for a First Offense as well as settling out of Court with the Provision that they list the Name of the Company, The Principals of that Company and it's Address as well as possibly the Principals Addresses in their regular Enforcement Alerts.
If this isn't the First Offense the Settlement will be considerably greater and you will have 12 months of Legal Fees that you need to pay for in the form of your Defense at the very least so it will cost considerably more than the 1/4 Million $ and will effectively hold the Business & It's Principals up to Ridicule @ the very least.
Col