Serial Port Boot Configuration

[Mark Teel]

I am trying to remotely debug a FreeBSD kernel, and it appears that the 
baud rate and other stty settings are being modified during system 
boot.  I have modified the /dev/ttyid0 device and the /dev/ttyld0 
device, yet their settings are being reset somewhere during reboot as 
well.  I have looked at the handbook, which states that initial settings 
are found in /etc/rc.serial, but there is no such file and no reference 
to it in "man rc.serial".

Where are boot serial parameters configured and by what are they set?

I need to set my ttyd0 port up to allow brkint, 115200 baud etc.

TIA,
Mark