marking diaresis and accent

[john]

Dear Funknetters, 

On my recent trip to South Sudan, I managed to
convinced a group of Dinka language specialists that it would be a good
idea to mark tone in a limited number of contexts (specifically high
tone in specific grammatical contexts which are always associated in
high tone in all forms and all dialects). This would be pretty rare,
occurring on maybe 1 or 2 percent of the vowels. The problem is that
they already mark voice quality with diaresis (aka umlauts, two dots
over the vowel), and this occurs on about a third of the vowels. The
most common way to mark tone in African languages is with an acute
accent, but this would create a complication in that some vowels would
need to be marked for both voice quality AND tone. This would be a bit
of a mess, aside from which I don't know of any fonts which have such a
symbol. I thought of using the Hungarian long umlaut (basically two
parallel acute accents) to mark both diaresis and acute accent
simultaneously (this is the diacritic function it has in Hungarian,
although both of the linguistic functions are completely different).
This was not a great hit with the Dinkas, I guess because they'd never
seen it before, but I suppose they might accept it if they were given
some kind of keyboard demonstration showing that it really isn't so
complicated. Another difficulty is that in Hungarian at least this
symbol is only used over <u> and <o>, but in Dinka it would have to be
used over all 7 vowels (the five basic ones and also ɔ and ɛ, which are
part of the regular orthography). Do any of you have any ideas of how to
deal with this problem of marking diaresis and tone (it can be something
other than acute accent, I don't really care) simultaneously and/or the
associated problem of how to write it on a computer keyboard? 

Thanks,


John