Greetings!
     Before connecting a modem to the IPC's serial
port(s), I figured it would be prudent to hook a
terminal up and verify the proper settings and
operation of that port.
     I changed "off" to "on" in the entries for
tty{a,b} in /etc/ttys.  Added the "local" option
to each (have also tried this *without* "local").
Ran ttyflags(8) on tty{a,b}.  Then kicked init
(kill -HUP 1).
     "Terminal" is set for 9600 8N1 as is evident
from ttys(5) and gettytab(5).  Terminal in question 
works when connected to another device (e.g., when
connected directly to a modem).
     Results don't appear to be consistent.
Sometimes I can get a login banner.  But, the
user name is not echoed and doesn't appear to
be "received".
     Trying to move characters directly to the device is
also inconsistent (cat foo > /dev/ttyb; cat /dev/ttya; etc.)
     I've tried two different IPC boxes to help rule
out hardware problems.  Anything else I should try?
Any known problems with the SCC's in these machines?

Thx!
--don