Does mount provide some way to add hooks such that
  mount /foo
can do some work to setup/create the necessary device file before
actually mouting it (the device file contains an ext3 partition).
I'm thinking of an fstab entry like
  /dev/bar  /foo     ext3     noexec,prehook=/sbin/makebar
In my case /dev/bar is really an LVM volume that needs to be activated
(it's on a USB drive) before the corresponding device can be used.
        Stefan