umount(ing) usbdrive mounted via gnome-volume-manager

[Carl Greco <carl.greco@gmail.com>]

I cannot umount a usb memory stick that was mounted with
gnome-volume-manager while the file browser, Nautilus 2.8.2, is running
either by right clicking the desktop usbdisk icon or the folder in the
file browser.  Error message: "umount: /media/usbdisk: device is busy". 
The following is the attempt to execute pumount with debug option:

    $: pumount -d usbdisk
    checking whether usbdisk is a mounted directory
    checking whether /media/usbdisk is a mounted directory
    resolved mount point /media/usbdisk to device /dev/sda1
    resolved /dev/sda1 to device /dev/sda1
    policy check passed
    Executing command: /bin/umount /dev/sda1
    umount: /media/usbdisk: device is busy
    umount: /media/usbdisk: device is busy
    umount program terminated with status 256
    Error: umount failed

The usbdisk folder is not open in the file browser.  The "fuser -m
/dev/sda1" does not list any processes using the usbdisk. Umount is
successful if file browser is closed first.  I am a member of the
plugdev group, the /etc/mtab entry for /media/usbdisk is assigned to my
uid,gid, and usbdisk is not listed in fstab. 

This should be possible.  I've been able to umount the usbdisk while
file browser is running on a ubuntu 5.10 system.  I'm running sarge with
packaged kernel 2.6.8-2-686. 

-- 
Carl