The behavior in the instance of having more than one language specified in the META tag of a page is not specified. IE 7, Chromium, and Safari 3.1 all fail this test. Firefox passes.
The html element in the test says: <html>. There is no HTTP Content-Language information. There is a meta tag that says <meta http-equiv="Content-Language" content="ko,zh,ja" />. The tests will react if Korean (ko) language is detected.
1. Launch Chrome, or Safari 3.1
2. Go to http://www.w3.org/International/tests/sec-lang-decl-6 or
3. Observe "Styling with :lang" section
Background color is white
Should be green
This is being tracked by Chromium as http://code.google.com/p/chromium/issues/detail?id=3180
According to the HTML5 spec, http-equiv Content-Language containing a comma should be ignored: http://dev.w3.org/html5/spec/Overview.html#pragma-set-default-language
Also, when falling back to the HTTP header Content-Language, if it contains multiple languages, the computed lang should be unknown: "In the absence of any such language information, and in cases where the higher-level protocol reports multiple languages, the language of the node is unknown, and the corresponding language tag is the empty string."
The w3 tests seem updated to reflect this: