I installed XFCE 4.8, but have problems with the directory icon themes in Thunar. I'm using a home-made theme, that worked well in earlier versions of Thunar. In the new version, it uses the proper icons, except for the directories, which revert to the default Gnome icon theme. This is the case for all normal directory icons (desktop and home show up properly), in all sizes.

The icon theme works fine in Nautilus and PCManFM. Why is Thunar not recognising them?