In Google Webmaster Tools, I'm getting 9 errors per sitemap complaining about the sitemap not containing a language setting (which should be English or US English -- EN).
I've looked through old threads about db settings, options and the php files, but they no longer seem to contain entries to specify a language.
So first, are these errors fatal? Like serious enough to trigger skipping the site by Google?
And second, is there a way to fix this, like by setting an option or adding a line to the plugin?