feature request: sorted rss feed over multiple namespace sites

[horstjens]

Hi this is a feature request, i am also thankful for hints of how i can fix this myself ( my php skills are not great)
i blog with dokuwiki and have namespaces for each year ( 2016, 2017 etc) in each namespace i have several pages, one for each blog entry. ( like :blog:2017:0401_first_april_blogpost, :blog:2017:1224_christmas etc)

Thanks to the feed plugin, i can create sorted automated rss feed, but for one year (=namespace) only:
{{blogfeed>:blog:2017|feed for all 2017 blog entries}}

If i try to create an rss feed over all of my namespaces (=years) i get an complet unsorted feed, with entries in a wild order, mixed between years

{{blogfeed>:blog|feed for all years}}

I want that this multi-namespace feed is also sorted just by inverse namespace and page name. How can i do that ?