Changing (and worse, recycling) 3166 Alpha-2 codes puts us in mind of all sorts of database-related disasters, but that's not all. Think of:
. Top-level Internet domains. Imagine the possibilities for spoofing during the "transition period".
. Postal-code country prefixes, which are programmed into postal sorters, post-office procedure and routing manuals, etc. Imagine how much mail meant for Serbia might be delivered to the Czech Republic.
Conversely, addresses that might still have CS for Czechoslovakia, when passed through an updated sorter, could wind up in Serbia.
Don't forget historical sources where you might need to use Alpha-2 codes for both the former Czechoslovakia and for Serbia.
Stefan
