backward compat in /etc/fstab?

[Mipam]

Hi,

In 5.2 when you wished to make mdmfs in an /etc/fstab entry, you were 
actually using the compatibility mode for the old mount_mfs. It was not 
possible to set permissions and ownerships in an /etc/fstab entry.
So a workaround should be made then in /etc/rc.local
It this still the same in 5.3 or will the compatibility mode be removed so 
that proper permissions and ownership can be set in an fstab entry?
Bye,

Mipam.