sgmlop: malformed charrefs?

[Magnus Lie Hetland]

According to The Sgmlop Module Handbook [1], the handle_entityref()
callback is called for "malformed character entities". What does that
mean, exactly? What is a malformed character entity? I've tried
mis-spelling them (e.g., dropping the semicolon), but then they're
(quite naturally) treated as text/data, with handle_data(). I've tried
to use number that is too great, or (equivalently, it turns out) to
use names instead of numbers, such as &#foo;. In these cases, I only
get an exception, because the number is too high...

So -- how can I produce a malformed character entity? I've tried to
read the C code, but I can't say that left me any wiser on the
subject; it doesn't seem to have any special-casing for this that I
can find.

And another thing... For the case where a numeric reference is too
high (i.e. it can't be translated into a Unicode character) -- is it
possible to ignore it (or replace it, as with encode/decode)? I'm
trying to write a parser that will accept *any* input text without
complaining -- but simply trapping this exception would seem to
disrupt the parsing process...

Thanks,

- Magnus

-- 
Magnus Lie Hetland               Time flies like the wind. Fruit flies
http://hetland.org               like bananas.         -- Groucho Marx