A few days ago, in Oh, the enumeration!, I wrote about some changes to the enumeration of our Spanish Traditional sort locale that would be new for Vista. What I wrote is that callers to EnumSystemLocales would have to pass the LCID_ALTERNATE_SORTS flag to return 040a (Spanish Traditional sort) in Vista. Well, based on customer feedback, we have decided to revert that change. That is, EnumSystemLocales will continue to behave as it behaved in XP, returning 040a even without the LCID_ALTERNATE_SORTS flag.
However, the name-based API counterpart, EnumSystemLocalesEx, will require the LCID_ALTERNATE_SORTS flag in order to return es-ES_tradnl, which is the locale name identifier for Spanish traditional sort (040a). That means that the LCID-based API and the name-based API are not strictly in parity, with EnumSystemLocales respecting previous behavior and EnumSystemLocalesEx introducing the desired behavior -- in which Spanish Traditional sort is properly treated as an alternate sort locale -- instead.