bradcrumbs dont work properly on external usb-hdd

[brainpower]

Say, I have the following path "/media/1000/test/test2"
When I go to "test2" by clicking the icons, it works all fine,
but if I'm in "test2" and want to go to the parent "test" by clicking the breadcrumb,
the "folder-view" below goes all blank, instead of showing the folder "test2" which should be there...

http://img714.imageshack.us/img714/6728/marl0.png
http://img23.imageshack.us/img23/9389/marl1.png
http://img825.imageshack.us/img825/5792/marl2.png

Since I've added /media/1000 as 'XDG_DOWNLOAD_DIR="/media/1000"' in ~/.config/user-dirs.dirs
I tried to set that back to the default and the breadcrumbs worked how they should...
It works like a charm with the other folders set in user-dirs.dirs, though.
For example 'XDG_VIDEOS_DIR="/media/1000/Videos"' works fine.
Seems only to break the breadcrumbs, if you set one of it to the root of a harddrive... or to a mountpoint...