starting manual dialup on ipcop from one of the green hosts

I want to use ipcop as a firewall, what I'd like is
to find some way to manually startup ppp thru the modem
on the ipcop box if any of the hosts on the green side
run a script. This is instead of using dial on demand
because I don't like the idea of a simple http request
from a browser being able to make the modem dial out
since that might happen when I'm not there.

I figure it would be a lot less likely to dial out by
accident if you have to run a script from the command
line. Is there a way to do this? What I"d like to avoid
is having to ssh to the ipcop host and then run pppd manually,
it would be really nice for xinetd to watch a port
on the ipcop box and run pppd if a particular port is
hit from the green side or kill pppd if a different unused
port is hit. Later I'll be using cable modem so this
will be of less use.

Mark