When you have no Accept-Language header or an unsual one (say, Finnish only), then http://jigsaw.w3.org/css-validator/ looks like http://www.google.com/search?q=cache:jigsaw.w3.org/css-validator Please see the attached image. I don't think this is a good idea. The default version sent to the reader should be English.
(IMAGE/gif attachment: no-accept-lang.gif)
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