Automating a multicast

I have a customer (multi-district school system), and they're currently
using Ghost as an imaging solution. There are a LOT of inefficiencies in
how they're using it, and I'd love to be able to convert them to ZEN imaging
(they're using several ZEN 7 components already), but I can't find that the
following is possible using ZEN:

They want to be able to schedule a multicast, and tie it to a series of
workstation objects (or to a workstation group), force a remote wake-up (or
reboot) for this group, and have them connect to the multicast session
automatically. I know how to initiate multicast sessions from both the
Imaging engine locally, or through a server, but haven't yet found a place
where I can specify that a series of workstations should become clients to
this session automatically when they restart. In essence, they don't want
to have to visit any of these classroom systems to force an image to the
entire room at night.

Thanks!

b