[db-wg] country attribute: "ZZ" for unspecified?

Note that this quote
    
    - ISO 3166-1 [1] specifies "ZZ" as "User-assigned code elements are 
    codes at the disposal of users who need to add further names of 
    countries, territories, or other geographical entities to their in-house 
    application of ISO 3166-1, and the ISO 3166/MA will never use these 
    codes in the updating process of the standard.".    
    
    [1] <http://en.wikipedia.org/wiki/ISO_3166-1>

is a bit short on the details. The standard ISO 3166-1:2006(E/F) actually says:

  8.1.3   User-assigned code elements

  If users need code elements to represent country names not included
  in this part of ISO 3166, the series of letters AA, QM to QZ, XA
  to XZ, and ZZ, and the series AAA to AAZ, QMA to QZZ, XAA to XZZ,
  and ZZA to ZZZ respectively, and the series of numbers 900 to 999
  are available. These users should inform the ISO 3166/MA of such use.

Short of buying the standard documents, some more details about
3166 and user-assigned code elements can be found at:
<http://www.iso.org/iso/customizing_iso_3166-1.htm>.

	jaap