[xubuntu] Change icons of executable itself (no .desktop!)

I want to change the infamous VLC icon with something better. I edited /usr/share/applications/vlc.desktop and I changed the Icon entry.
This works for the Whisker Menu and every other window of Xfce.
However, in the Window Buttons part of the panel (where active windows are listed) and in the Indicator plugin (system tray), the standard VLC icon is shown.
I guess this is because the icon is hardcoded in the binary executable?

If that's the case, I guess I need a software like Resource Hacker for Windows: what program do you suggest for linux? (please don't say Wine, thanks).

If that's not the case, then what steps should I take?