According to a WEB UPD8 post from july 2011, it is possible to install Faenza-styled icons on LibreOffice toolbar.
I can't install Faenza the traditional way on LO 3.5 (i.e., changing the toolbar icons from Crystal or Tango from inside the application's "Options" menu) and now those icons are broken.
Faenza was already installed but the update removed everything.
Update manager, today updated LO to 3.5 also here (Ubuntu 11.04). As I was using same icon theme I noticed same issue.
Just copying faenza archive over /usr/share/libreoffice/share/config/images_crystal.zip was not enough. Comparing icon theme archives from LO 3.5 with faenza set, revealed two possible misplacements:
I expect that first one was responsible for this issues, although I changed both: download link (3.6 MB)
So after downloading this archive place it as /usr/share/libreoffice/share/config/images_crystal.zip and then setting view to crystal should show faenza icons again :)
This doesn't bring back Faenza icons to LibreOffice (if they had been there), but this should fix its icons:
You could try to (re)install the usual icon theme libreoffice-style-human (click this link to do so) and choose it in Settings as follows:
Start LibreOffice and open the appropriate settings Dialog:
Choose the correct icon theme:
Does this help?