Last time I looked, installboot ran out of 
/usr/mdec and if you wanted serial bootblocks, you installed 
a custom biosboot*com0* file .

I just went to install them and they've vanished - a bit of digging 
shows postinstall thinks they are now obsolete:

0rasputin@lb:ssh$ grep mdec /var/db/obsolete/base
./usr/mdec/wdboot
./usr/mdec/sdboot
./usr/mdec/installboot
./usr/mdec/fdboot
./usr/mdec/bootwd
./usr/mdec/bootsd
./usr/mdec/bootfd
./usr/mdec/biosboot_resetvideo.sym
./usr/mdec/biosboot_ps2.sym
./usr/mdec/biosboot_com0_9600.sym
./usr/mdec/biosboot_com0_57600.sym
./usr/mdec/biosboot_com0_38400.sym
./usr/mdec/biosboot_com0_115200.sym
./usr/mdec/biosboot_com0.sym
./usr/mdec/biosboot.sym

So presumably it clobbered them...
Is there another way of getting a serial console working now,
or have the files just moved? Thanks.

-- 
'Almost 48 hours without an exploit in the default install'.
Rasputin :: Jack of All Trades - Master of Nuns