SunOS 4.0 dialin/dialout?

[NETNEWS]

I have a Sun 3/50 running SunOS 4.0 and I'm trying to get ttya and/or ttyb
to be able to both dialin and dialout.

I've reconfigured the kernel and set the zs0 flags to 0x0, setup my hayes
modem per the instructions in the Systems Administrators Manual, and
checked to make sure the cable has all the needed pins.  I set the
/etc/ttytab file so that the baud settings are correct and the lines are
"off" (no getty).

I have no problems dialing out, but when I dial in I get no login prompt.
I've done this on a machine running SunOS 3.2 with no problems, has 4.0
changed?  Is there something I'm doing wrong?  

Thanks,

Ray Roux