There's no solution to this yet that we're aware of.
The problem, of course, is that these barcodes are not listed in Amazon, and non-Amazon data sources is a feature we have yet to implement, since there are so many other features we have to implement first (the usual suspects: iTunes, web, sharing, etc).
As I always say, support for countries like Belgium are on the list, but it's a long list.
That said, you might try doing a title search. It's not as cool as barcode scanning, but it does get around regional barcodes, which is often the only issue.