XML processor behavior with unused NS declarations

Is a namespace-aware XML processor permitted to drop a namespace declaration 
when no elements or attributes in that namespace are used within the scope of 
the declaration?  Say, given this example from the RDRa Primer:

   <div xmlns:dc="http://purl.org/dc/elements/1.1/">
      <h2 property="dc:title">The trouble with Bob</h2>
      <h3 property="dc:creator">Alice</h3>
      ...
   </div>

there's no danger of the processor dropping the 'xmlns:dc' declaration, correct?

I looked at the Namespaces in XML recommendation, and it doesn't mention 
omitting them.  A namespace-unaware processor would treat NS declarations like 
attributes and hence not drop them, so I reckon that a NS-aware processor 
should match that behavior as well, but confirmation from the cognoscenti is 
welcome!

Thanks
Chuck
-- 
Chuck Bearden ( ; 713.348.3661)
XML Engineer, Connexions
http://cnx.org/