change hyphenation rules?

That does the trick as well and it is something I can be sure of it has no other unwanted results!

Sorry for reacting so late – an unexpected overload of work. Also, I didn't want to risk that a change in settings would ruin my work in progress.

The problem for me was not the doubling of hypens as in the example given:

   Oost-

   -Azië,

but in the fact that the words with a dash in it were not hyphenated at all at the spot of the dash. For instance, I got:

   Mrs. John-

   son-Peterson

instead of

   Mrs. Johnson-

   Peterson,

Even if the latter would produce a better composed paragraph.

Nevertheless, I changed hunspell to proximity and that seems also to do the trick in my case:

   We waren afgelopen jaar in

   Oost-Friesland op vakantie waar we

   veel plezier hadden.

became:

   We waren afgelopen jaar in Oost-

   Friesland op vakantie waar we

   veel plezier hadden.

which is exactly what I would want here.

However, with three book projects going and nearly finished, I feel a bit wary to do this. I don't know what the difference is between hunspell and proximity. (I even hardly know what they are.) Will changing this have other effects on ongoing projects, or on older, finished projects apart from things like I gave in the examples?

Also see my answer to Willi Adelberger below.