There's currently a discussion going on on the Unicode list (access
details at http://www.unicode.org/mail-arch/ ) about how to encode
notation used in German dialectology. The discussion has centred on
two topics:

1) Representation of the diacritics for the openness and extreme
openness of vowels, as seen in Section 2.1 of
http://www.uni-wuerzburg.de/germanistik/spr/suf/baydat-udi/pdf/Lautschrift.pdf
. Now to me, the diacritic for openness shown there is simple the IPA
diacritic. Othere have argued that it's an ogonek or a subscript iota.

Is there any relevant tradition of deliberately using ogonek in
preference to the IPA diacritic? Is there any likelihood of it being
some different but vaguely similar mark?

2) The use of ties for more than two letters. Now the IPA allows the
use of ties for affricates and diphthongs, but what examples are there
in the literature for it being used for sequences of three (or more)
segments? Possible examples of affricates that came to mind are an
aspirated affricates (e.g. tSh rather than tSH) and a prenasalised
bilabial trill, but these would normally be written with a superscript
'h'or 'm'. The example mentioned was rather less formal than IPA - it
was a tie for the letter of the German trigraph 'sch'.

Richard.