Freeze after unmounting ntfs usb drive

[nbl]

After running a python script on my usb drive (NTFS), unmounting it using contextual menu from the desktop's icon cause a complete freeze of the computer. No virtual terminal available. Necessary to reboot by hardware switch.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: linux-image-2.6.32-33-generic 2.6.32-33.70
Regression: Yes
Reproducible: Yes
ProcVersionSignature: Ubuntu 2.6.32-32.62-generic 2.6.32.38+drm33.16
Uname: Linux 2.6.32-32-generic i686
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.21.
Architecture: i386
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: Intel [HDA Intel], device 0: AD198x Analog [AD198x Analog]
   Subdevices: 2/2
   Subdevice #0: subdevice #0
   Subdevice #1: subdevice #1
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: nico 1843 F.... pulseaudio
CRDA: Error: [Errno 2] Aucun fichier ou dossier de ce type
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xfe9dc000 irq 16'
   Mixer name : 'Analog Devices AD1984'
   Components : 'HDA:11d41984,10280211,00100400'
   Controls : 30
   Simple ctrls : 18
Date: Mon Jul 18 17:34:07 2011
HibernationDevice: RESUME=UUID=743975f4-2180-4e56-9edd-b89f1128cd8d
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
IwConfig:
 lo no wireless extensions.

 eth0 no wireless extensions.

 vboxnet0 no wireless extensions.
MachineType: Dell Inc. OptiPlex 755
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.32-32-generic root=UUID=1e08c3ed-63c1-430c-b0cf-4e9ba9e939a7 ro quiet splash
ProcEnviron:
 PATH=(custom, user)
 LANG=fr_FR.utf8
 SHELL=/bin/bash
RelatedPackageVersions: linux-firmware 1.34.7
RfKill:

SourcePackage: linux
dmi.bios.date: 08/04/2008
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A11
dmi.board.name: 0GM819
dmi.board.vendor: Dell Inc.
dmi.chassis.type: 6
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA11:bd08/04/2008:svnDellInc.:pnOptiPlex755:pvr:rvnDellInc.:rn0GM819:rvr:cvnDellInc.:ct6:cvr:
dmi.product.name: OptiPlex 755
dmi.sys.vendor: Dell Inc.