Error detaching: helper exited with exit code 1

[cybernet]

after i try to unmount an USB stick within gnome-panel interface with "safely remove drive" it says writing data to "device name"

and then an error appears

Error detaching: helper exited with exit code 1: Detaching device /dev/sdb
USB device: /sys/devices/pci0000:00/0000:00:1d.7/usb2/2-3)
SYNCHRONIZE CACHE: OK
STOP UNIT: FAILED: No such file or directory

i never lose the data stored on the device or the date previously copied ( written )
but i get this error

what's causing it ?

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: gnome-panel 1:2.30.2-0ubuntu0.2
ProcVersionSignature: Ubuntu 2.6.32-37.81-generic 2.6.32.49+drm33.21
Uname: Linux 2.6.32-37-generic x86_64
Architecture: amd64
Date: Fri Dec 23 13:45:18 2011
InstallationMedia: Ubuntu 10.04.3 LTS "Lucid Lynx" - Release amd64 (20110720.1)
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: gnome-panel

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[aoandr (t-launchpad-nbs-eng-ru)]

Seems to be related to bug #466575: "secure remove of external USB-HDD produces error"

[cybernet (cybernet2u)]

will someone try to fix it ?