I have 'years' (flat) and 'regions' (hierarchical) taxonomies, e.g.:
Years: - 2010 - 2011 Regions: - Europe -- France -- Italy -- Russia -- ... - Asia -- China -- Japan -- Iraq -- ...
The problem is that after selecting a year, the regions list is flattened as if continents were excluded:
Years [-]: - 2010 [-] Regions: - France [+] - Italy [+] - Russia [+] - China [+] - Japan [+] - Iraq [+] - ...
... so I can't display the entries from selected year and entire continent.
EDIT: What's interesting - if I firstly pick a continent, and then year, it's possible to display entries for e.g. Asia+2010 criterions (the URL I get: http://example.com/?region=asia&year=2010)