Spec question

Section 5.3 "Uniqueness of Attributes" explicitly states that the
following is legal:
<x xmlns:n1="http://www.w3.org"
     xmlns="http://www.w3.org" />
    <good a="1"     b="2" />
    <good a="1"     n1:a="2" />
  </x>

however, in the second "good" example both attribute's namespace names
are equivalent (the default of: "http://www.w3.org" and the explicit
"n1"="http://www.w3.org"). So it seems to me that it really is illegal.

Please clarify...

Peter