Note that the namespace declaration for the builtins
namespace is in structures.dtd so it can be customised
stubs for built-in primitive datatypes follow
pattern matches production 33 from the XML spec
pattern matches production 7 from the XML spec
pattern matches production 5 from the XML spec
pattern matches production 6 from the Namespaces in XML spec
pattern matches production 4 from the Namespaces in XML spec