Janus, how about submitting a patch for this bug including a testcase?

As Janus Weil found out:
http://gcc.gnu.org/ml/fortran/2007-06/msg00488.html

If a namelist in a procedure contained in a module procedure contains a private item as element, a bogus error message is printed:
   Error: PRIVATE symbol 'r' cannot be member of PUBLIC namelist at (1)

This fails if the symbol is not in the parent, but in the parent->parent
namespace.
One solution would be to add
    && !(sym->ns->parent->parent == nl->sym->ns)

module mod
  real, private :: r
contains
  subroutine x
  contains
    subroutine y
      namelist /n/ r
    end subroutine y
  end subroutine x
end module mod
end