This is a first cut of my callback tool. Highly BETA, many rough edges.

You call it from "login.config" like this:

#
# callback experiments
#
cback-gert--/usr/sbin/callback -S 11223344

to call you back on "11223344" upon entering of a login name of
"cback-gert". If you don't specify a number on the command line,
the program will ask.

If you don't specify a username but "*", things will break: callback
will loop forever, calling you again and again (skipping login.config
upon the second connect doesn't work yet), because it will *always*
call callback...

Use it for your own fun, and on your own risk.

NEW: there is a callback man page ("man 8 callback") now.

gert