Xfce 4.4 - Icon problem

[roger]

Thanks Erik.

I had tried strace on xfce-setting-show but couldn't find anything useful.
Anyway, following your advice, I did another strace, this time on the panel 
after having killed it (15).

I looked for Rodent in the output and found out that the program tried to 
access it from:
- ~/icons/
- ~/.local/share/icons/
- /var/lib/menu-xdg/icons/
- /usr/share/icons/
- /var/lib/menu-xdg/pixmaps/
- /usr/share/pixmaps/
and that's all.
So /usr/local/share/icons/ was just ignored! (note: all Xfce modules were 
installed in /usr/local but gtk-xfce-engine in /usr)

I made a symlink from /usr/local/share/icons to ~/.local/share/ and restarted 
Xfce. Then my panel, as well as xfce-setting-show, got their icons back.
The right-click Desktop Menu now displays many more icons than previously. 
However most of the KDE's one are still missing as well as some classical 
ones such as XEyes.
However, I don't have any icon issue when logged in with either KDE or Gnome.

Regarding the panel, with my kill/strace test, I've ended up with half of its 
setup lost. I'm not really sure how the panel is supposed to save its config 
but I guess that the setup was saved at the very beginning of the slow 
execution under strace, while not all pluggins were loaded, and that 
unfortunately I logged out before the "save config" were kick off again. More 
work on reliability may be needed on that side...

Cheers,
Roger