xquery query

What should the following query evaluate to?

(<a/>)/a

From my reading of the specification, and from most implementations I have tested, this should return the empty sequence.

However, Microsoft's implementation returns <a/>.  This really doesn't seem right to me.  (Note (<a/>)/. also evalutes to <a/> on Microsoft's implementation -- this makes sense, but it doesn't make much sense in conjuction with the above result!)

Which is correct?