strange umount behaviour

[Lukas Ruf <ruf@rawip.org>]

Dear all,

very strange to me I have problems umounting a previously mounted
device.  I make use of unstable.

The output is:
komsys-pc-lr:~!75> mount
rootfs on / type rootfs (rw)
/dev/root on / type ext3 (rw)
proc on /proc type proc (rw)
devpts on /dev/pts type devpts (rw)
/dev/hda1 on /boot type ext3 (rw)
/dev/hda3 on /var type ext3 (rw)
/dev/hda5 on /home type ext3 (rw)
/dev/hda6 on /www type ext3 (rw)
/dev/hda7 on /scratch type ext3 (rw)
usbdevfs on /proc/bus/usb type usbdevfs (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
komsys-pc-lr:~!76> mount /cdrom
komsys-pc-lr:~!77> umount /cdrom
umount: only root can unmount /dev/cdrom from /cdrom
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
komsys-pc-lr:~!78> ls -l /bin/*mount*
-rwsr-xr-x    1 root     root        72488 Oct  7 17:46 /bin/mount*
-rwsr-xr-x    1 root     root        36680 Oct  7 17:46 /bin/umount*


Does anyone know why and how I can solve this problem?

Thanks in advance,
-- 
Lukas Ruf
http://www.lpr.ch                                 http://www.maremma.ch    
    http://www.{{topsy,nodeos}.net,{promethos,netbeast,rawip}.org}
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