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.