While poking around in the shared source RSS module for Sitecore, I found that several aspects of the “static feeds” feature loose language context during publishing. This only effects static feeds whereby the rss.xml file(s) are written to disk and linked-too directly. The processes is kicked-off my hooking into the publishing-end event.

While the similar method Context.Database.GetItem retrieves an item in the same language as the context item, it appears that SelectItems(selector, predicate) does not. So if you are in a language other than ‘en’ English, you will probably retrieve the ‘en’ version of your non-‘en’ language items, resulting in large areas of missing data.

I’m not sure if this only effects SelectItems()  when run outside of the context of a web request, or if it happens all the time, but the work-around is to explicitly change your context.language before calling SelectItems().

ContextItem.Database.SelectItems(selector, predicate);     …..will return ‘en’ language items regardless.

Instead you must use:

Sitecore.Globalization.Language.Current = ContextItem.Language;
ContextItem.Database.SelectItems(selector, predicate);    

….which then retrieves items in the same language of contextItem.