Hi koorbnats,
If you check the bottom portion of that article, it addresses the region limitations of digital copies:
iTunes Digital Copies aren't available in every country.
You must use a Digital Copy code in the iTunes Store country where the packaging says it will work. For example, you'll need a U.S. iTunes Store Apple ID to use a code from a U.S. DVD, and you'll need an Australian iTunes Store Apple ID to use a code from an Australian DVD.
Apple Support: Redeeming an iTunes Digital Copy
http://support.apple.com/kb/HT1539
Regards,
- Brenden