controlling a modem

[hall@research.att.com (Bob Hall)]

I want my MCL program to be able to use a modem to access another system,
doing stuff like I currently do manually: dialing up, logging in, navigating
a file system, transferring files to/from the Mac, executing remote commands,
etc.  I'm envisioning a three-part architecture:

  HIGH-LEVEL-CONTROLLER <===> MODEM-CONTROL-OBJECT <===> ACTUAL-MODEM

This message is asking for techniques for implementing the middle object.
(e.g., if the HIGH-LEVEL-CONTROLLER were me, then MODEM-CONTROL-OBJECT could be
Versaterm).  The problem is that I don't know how to interface MCL to Versaterm
or any analogous piece of software.  Alternatively, if the middle object
can be implemented in MCL itself, that would be even better. 
The middle object takes in (from the left) high-level command line strings
(such as "dial 18005555555" or "cd /usr/hall/stuff" and puts
out output line strings (e.g. "connect 9600" or "password:"), while it talks
in modemese out the right-hand side.

Here are my specific questions:
- Does anybody know of a technique I can use to do this, short of writing
  my own raw modem control software from the ground up?
- I have a Mac with an attached Telebit (9600 baud) modem.  Manually, I use
  it via Versaterm PRO, usually in VT220 emulation mode.  Is it conceivable
  I could do something by sending Versaterm apple events or something?
- Does anybody know of some available MCL code that does anything interesting
  with a modem?

Thanks,

-- Bob Hall