I suspect there is a little problem in Italian hyphenation. With expression like "quell'impossibilità" (with an apostroph) the possible points should be "quel-l'im-pos-si-bi-li-tà", but Prince seems to recognise only the first point "quel-l'impossibilità". If it is so, I think it should be corrected, Italian abounds in long words and in such cases the effect can be rather unpleasant.

Thank you, we will take a look at this.

Fourteen years ago (time passess...) I found a similar problem in Lout. I don't know if this is relevant, but anyway this was my solution:

https://lists.gnu.org/archive/html/lout-users/2001-09/msg00068.html

Update: I checked with "hyphens: prince-expand-all" (I have discovered just now that option) and I can confirm: hyphenation points after the apostroph are not recognised (neither in Italian nor in French).

Update 2: Prince uses the version 4.8 of Italian TeX patterns; the most recent is 4.9 but that has (unfortunately...) no relationship with the problem.

We have a fix for this issue now, which operating system are you running Prince on?

Great, thank you! I am using at the same time Ubuntu 12.04 64bit and Windows 64bit.

We have latest builds for Ubuntu ready now, but Windows will need to wait until tomorrow.

Updated builds for Windows are also available now.

All is perfect, thank you again!