references in order of appearance (again)

[Mikko Huhtala]

I need to generate reference lists that are in order of the appearance of
the citations in the text. So far I have used preprocessing to add labels
(numbers) to each @Cite and then sorted the reference list using labels as
the key. There are two problems with this: first, the labels are sorted as
strings, so '2' comes after '19' and before '20' etc. and second,
consecutive reference numbers come out as separate labels, eg. (1, 2, 3,
4, 7) instead of (1-4, 7).

Is there some way around the sorting problem? The citations I can live
with, or fix by editing PostScript if I must. I know that adding the
feature properly to Lout is difficult (I'd still like to see it :-) 

Mikko