Having an empty /home directory on /dev/sdb3 is perfectly normal. You
are looking at the mount point for the disk that contains the
filesystem of your /home. That's what fstab is supposed to do: mount
the drive /dev/sdb5 over /home so that you see it as an normal
directory. And it looks it's not working, but you tell me that ubie
tells you that the filesystem is mounted. That's what puzzle me.

Do you see any messages about sd5 or home from the command "dmesg".
You could try : dmesg|egrep 'sd5|home|mount|filesystem|ERROR'

And check that the permissions on your /home are the following:
drwxr-xr-x user=root group=root.
The execute bit must be turned on for all if you want to be able to
access sub-directories.

If I list the permission of the device that contains my home
filesystems, it shows this:

pluton log # ls -ailgd /dev/sda3
3378 brw-r----- 1 disk 8, 3 Feb 21 12:40 /dev/sda3

My fstab entry for home shows this:
# /dev/sda3
UUID=ffffffff-ffff-ffff-ffff-ffffffffffff /home ext3
relatime 0 2