fstab has "user" option, but still cann't be mounted by non-root user

[yuanwei xu <xuyuanwei@gmail.com>]

Hello, below is one section of my fstab, I want my usb
harddisk(/dev/sdbx) can be mounted by the non-root,according the man
page of fstab,I set the "user" option,but still get error " mount:
only root can do that" when i try to mount it.


# /etc/fstab: static file system information.
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# /dev/sdb4       none            ext4    sw              0       0
UUID=e2f1534d-aecd-4f2a-a153-822ac4d73967	/media/usbdisk4_data
   ext4    user,exec,dev,suid,rw,noauto              0       0


i tried the command: $mount /dev/sdb4 /media/usbdisk4_data and $mount
/dev/disk/by-uuid/e2f1534d-aecd-4f2a-a153-822ac4d73967
/media/usbdisk4_data, but both were failed.
$ls -l /bin/mount output: -rwsr-xr-x 1 root root 84944  8月  3 22:02
/bin/mount, there is suid bit.

I have googled the problem, it seems there are no other actions needed
to do, but why it still failed?