For the scenario where you have two openbsd hosts, one connected to

the second with a serial null modem cable, what is the right device to

use when connecting using tip(1) from the first to a console on the

second?
These suggest that cua is the right device to use:
http://www.openbsd.org/faq/faq8.html#TTY

http://marc.info/?l=openbsd-misc&m=115868967631296&w=2

http://marc.info/?l=openbsd-misc&m=118764543712174&w=2
But for me, using cua00 fails with "missing phone number" message

while tty00 works:
molodetz$ tip -19200 tty00

can't open log file /var/log/aculog.

connected
OpenBSD/i386 (sinoptik.sancho2k.net) (tty00)
login: ~

[EOT]
molodetz$ tip -19200 cua00

can't open log file /var/log/aculog.

missing phone number

[EOT]
If cua00 is the right device to use when connecting out, why the

missing phone number error?
DS