xs:dDuration in F & O

Is there a type

  xs:dDuration

or is this a bug (three different occurences in
http://www.w3.org/TR/xpath-functions/ ) ?

-- 
Cheers,
Dimitre Novatchev
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Truly great madness cannot be achieved without significant intelligence.
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To invent, you need a good imagination and a pile of junk
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You've achieved success in your field when you don't know whether what
you're doing is work or play