I have an iPod Classic 120GB. When I use Nautilus (Gnome file manager) to eject the iPod (not unmount), I get the error "Connect eject volume", "There was an error ejecting the volume or drive", "org.freedesktop.Hal.Device.UnknownError: An unknown error occurred".
The iPod actually gets ejected properly (iPod recognizes the eject command and goes through its own eject process). However, the USB Drive itself stays around in Nautilus until I physically disconnect it from my computer.
I also noticed that "hal-device" still lists the iPod with a udi '/org/freedesktop/Hal/devices/storage_serial_Apple_iPod_000A2700138FC7CF_0_0'. However, the volume itself ('/org/freedesktop/Hal/devices/volume_uuid_3141_5926') isn't listed anymore.
I don't know what other information I can give, but if pointed in the right direction I should be able to get any necessary information.
Since no data is corrupted and the iPod actually thinks it's ejected, this isn't a high priority. However, novice users will be very confused and concerned about this (I know I was for a little, and I'm not a novice user).