Proposed resolution (04/01):

Change _N4567_.5.1.1 [expr.prim.general] paragraph 7 and A.5 [gram.expr] from

nested-name-specifier:
class-or-namespace-name :: nested-name-specifier_opt
class-or-namespace-name :: template nested-name-specifier

class-or-namespace-name:
class-name
namespace-name

to

nested-name-specifier:
type-or-namespace-name :: nested-name-specifier_opt
type-or-namespace-name :: template nested-name-specifier

type-or-namespace-name:
type-name
namespace-name

This resolution depends on the resolutions for issues 245 (to change the name lookup rules in elaborated-type-specifiers to include all type-names) and 283 (to categorize template type-parameters as type-names).