"No style sheet found" for application/xhtml+xml

http://jigsaw.w3.org/css-validator/ cannot find a stylesheet
when the content-type is application/xhtml+xml.
Example:
 http://www.unics.uni-hannover.de/nhtcapri/ruby-annotation.xhtml

Is this a known issue?

Received on Thursday, 30 March 2006 14:27:00 UTC