>The meaning of and similar items is a semantic issue. ISO 8879
>does not concern itself with the semantics of entities.
This is true, if you are talking about entities used within
content. What about if you have a non-breaking space within
markup (say separating attributes values) or a zenkaku space within a
DTD? There are cases such characters, when they occur inline, can
That is why it's good to map them to SEPCHAR.