Header number separator

["Jeff Smith" <ascarel@gmail.com>]

Hi,

Some time ago I had a query on the list about roman numbering in
headers. Once I got my answer, I asked something else relatively
unrelated but in the same thread. It's probably bad etiquette, so I
figure that is why it has remained unheeded. I'd like to submit my
second query again.

I have a problem with the separator in header numbers. I want to
use a different separator between chapter and section numbers (-), than between
section and subsection numbers (.).

So, assuming I'm using roman numerals for chapters, I'd like numering
of sections to be I-1, I-2, I-3, etc., of subsections to be I-1.1,
I-1.2, I-2.1, I-2.2, I-2.3, etc.

Now when I use \setuphead for section and subsection blocks with
different [separator=] attributes:

\setuphead[section][separator=-]
\setuphead[subsection][separator=.]

... it defines the separator for the _whole_ header level, not the
number position within any relevant header. So I get this instead:

sections are numbered I-1, I-2, I-3, etc.
subsections are numbered I.1.1, 1.1.2, I.2.1, I.2.2, I.2.3, etc.

Is there a way to achieve what I want to do?

Thanks!
Jeff