mounting an xfs partition

[Amadeus W. M.]

I just added a new disk to my pc and I made 2 xfs partitions. Then I
created directories /backup and /data2 and I put these lines in /etc/fstab:

/dev/hda1               /backup                 xfs     defaults        1 2
/dev/hda2               /data2                  xfs     defaults        1 2

I want normal users to be able to write to those partitions so I did

chown root:users /backup
chmod 775 /backup

and similarly for /data2. However, when I mount the partitions (as root)
the permissions change to 755. 

14) root:~> ls -ld /backup/
drwxrwxr-x 2 root users 4096 Jan 24 20:32 /backup/
15) root:~> mount /backup/
16) root:~> ls -ld /backup/
drwxr-xr-x 2 root root 6 Jan 19 15:02 /backup/


What do I do? I'm puzzled especially because I have one more xfs partition
created in the yore days of FC4 (running FC6 now with kernel 2.6.19-1.2895)
with a similar entry in /etc/fstab:

LABEL=/data1            /data                   xfs     defaults        1 2

with the same ownership and permissions (775) that doesn't change
permissions when mounted. What gives?


Thanks!