The net.sf.click.extras.control.CountrySelect field generates a list which contains several countries multiple times (Belgium, Canada, Ireland, Japan, Luxembourg, Malta, Norway, Singapore, Spain, Switzerland, Thailand, United States).
This is because the source used to generate this list (Locale.getAvailableLocales()) contains multiple items (when there are sublocales).
This can be solved by manually filtering the list, or using a set. I solved it using a set.
in CountrySelect Line: 212
List optionList = new ArrayList();
Set optionList = new TreeSet(new OptionLabelComparator(getLocale()));
and removing lines: 223 and 224