On some linux systems I had a sorting bug in eZCountryType::fetchTranslatedNames. The sort order of all country selectors was incomprehensible. I located the problem (after hours of course g) in this call which exists since eZP 4.2.0:

usort( $countries, 'eZCountryType::compareCountryNames' );

According to the PHP Docu on http://www.php.net/manual/en/function.usort.php this should look like this:

usort( $countries, array( 'eZCountryType', 'compareCountryNames' ) );

After I changed that it worked very well.