Binary package hint: gnome-mount
Upon trying to mount a USB key, (...after I figured gnome-mount was being used instead of pmount, and that one needs to set --text and --no-gui on it to get --verbose to work...), I get this:
$ /usr/bin/gnome-mount -t -v -n --hal-udi=/org/freedesktop/Hal/devices/volume_uuid_46B7_08D5
gnome-mount 0.6
** (gnome-mount:13273): DEBUG: Mounting /org/freedesktop/Hal/devices/volume_uuid_46B7_08D5
** (gnome-mount:13273): DEBUG: read default option 'shortname=mixed' from gconf strlist key /system/storage/default_options/vfat/mount_options
** (gnome-mount:13273): DEBUG: read default option 'uid=' from gconf strlist key /system/storage/default_options/vfat/mount_options
** (gnome-mount:13273): DEBUG: read default option 'utf8' from gconf strlist key /system/storage/default_options/vfat/mount_options
** (gnome-mount:13273): DEBUG: read default option 'umask=077' from gconf strlist key /system/storage/default_options/vfat/mount_options
** (gnome-mount:13273): DEBUG: read default option 'exec' from gconf strlist key /system/storage/default_options/vfat/mount_options
** (gnome-mount:13273): DEBUG: read default option 'usefree' from gconf strlist key /system/storage/default_options/vfat/mount_options
** (gnome-mount:13273): DEBUG: Mounting /org/freedesktop/Hal/devices/volume_uuid_46B7_08D5 with mount_point='lutzky-usb', fstype='', num_options=6
** (gnome-mount:13273): DEBUG: option='shortname=mixed'
** (gnome-mount:13273): DEBUG: option='uid=1000'
** (gnome-mount:13273): DEBUG: option='utf8'
** (gnome-mount:13273): DEBUG: option='umask=077'
** (gnome-mount:13273): DEBUG: option='exec'
** (gnome-mount:13273): DEBUG: option='usefree'
** (gnome-mount:13273): WARNING **: Mount failed for /org/freedesktop/Hal/devices/volume_uuid_46B7_08D5
org.freedesktop.Hal.Device.Volume.InvalidMountOption : The option 'usefree' is not allowed for uid=1000
This box is an up-to-date gutsy machine installed from the Beta CD (not RC1), mounting the DOK with pmount works, mounting it on an RC1 box works, so this may be an issue for upgraders. How to fix?
This is fixed in 0.5.9.1-6ubuntu5, but if you are upgrading it requires you remove the /usr/share/hal/fdi directory first (or removing it and reinstalling). This latter fact is also alluded to in bug 130490. I'm attaching a tarball of the original fdi directory that still lists the usefree option.