I have Adsense installed on a number of sites, where one is the English version, and the others are internationalized (translated) versions of the English site. The ads are displaying just fine on the translated sites, but for some reason the English site does not display ads anymore since the end of April.

Can anyone tell me how this could have happened?

Also, it may or may not be related, but a site:www.domain.com command shows all sorts of incorrectly indexed pages (non existing URL's, which seem to be partial URLs, something I did not cause as the URL's seem to be chopped of at random points), and traffic has been down since the end of April as well.