port not working!!

[Brantley Coile]

Does anyone know anything about the serial port on the back of the
AT&T UNIX PC.  We are trying to use it for a terminal port but it will
hang after a random amount of time.  Sometimes it is in one of our programs, 
sometimes it is runnig the getty.  When it you try to 'stty' the port after
it hanges stty hangs.  When you kill stty it reports that it couldn't open
the port.

We are running System V release 1 version 3.0 (the most recent issue).

PLEASE!! If you know anything about it send me mail.