Language selection shows up in search box?

I have set language selection to "current language ande language neutral". If I search for, let's say "xyz" from Drupals standard search block form, the search result shows up correctly on the search results page. In the search box on that page (and also in the url) it shows:

"xyz language:en,und"

Is that how it is supposed to work? Seems a little bit strange and not so user friendly to add that string visibly.

And also: if I make a new search from the search results page and search for a new word using the search box on this page (deleting everything that was previously in the search box), then the i18n setting is no longer respected and "language:en,und" is not added to the search string in the search box (or url).

So, how should it work? A bug?

/Bengt