Mounting XFS with user_xattr on Debian linux-image-2.6.12-1-686-smp not working?

[Paolo Alexis Falcone <pfalcone@gmail.com>]

I tried to remount an LVM volume and another partition - both
formatted as XFS - with the user_xattr option, but mount reports that
it's not a valid option, e.g.

pfalcone@balaraw:~$ mount
/dev/mapper/balaraw-root on / type xfs (rw,sync)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
tmpfs on /dev/shm type tmpfs (rw)
usbfs on /proc/bus/usb type usbfs (rw)
/dev/md0 on /boot type ext3 (rw,nodev,sync,noatime)
/dev/mapper/balaraw-usr on /usr type xfs (rw)
/dev/mapper/balaraw-var on /var type xfs (rw,usrquota,grpquota)
tmpfs on /dev type tmpfs (rw,size=10M,mode=0755)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
/dev/mapper/balaraw-home on /home type xfs (rw,usrquota,grpquota)
/dev/sdc1 on /media/usbdisk type xfs (rw,noexec,nosuid,nodev)
pfalcone@balaraw:~$ sudo mount -o remount,user_xattr /dev/sdc1
mount: /media/usbdisk not mounted already, or bad option
pfalcone@balaraw:$ sudo mount -o remount,user_xattr /dev/mapper/balaraw-home
mount: /home not mounted already, or bad option
pfalcone@balaraw:$ uname -a
Linux balaraw 2.6.12-1-686-smp #1 SMP Wed Jul 20 22:42:26 UTC 2005
i686 GNU/Linux

Is the user_xattr flag disabled already for XFS in Debian's 2.6.12 kernel image?

-- 
Paolo Alexis Falcone
pfalcone@gmail.com