getty repeating to quickly

[Dave]

Hello,
    I've got a box running 6.0-RELEASE. I'm trying to hook serial consoles 
in to it, and have set up /etc/ttys and /boot/device.hints to allow me to do 
this. Yet, in /var/log/messages i keep seeing this error:

"Init: getty repeating to quickly on port /dev/ttyd0, sleeping 30 secs"

This is a repeating msg and i never get my serial console. I've confirmed 
that the port is showing up via dmesg, the system's bios has it on the 
correct i/o address and irq, and the pnp option is turned off. Any ideas?
Thanks.
Dave.