> I achieved connection on the serial only at
> 9600.(both on bootprom and NetBsd session)

I use 38400 baud rate for both eprom (hardware) and tip/tty (serial
console) settings for IPC, IPX, and SS5.  Never had problems; only
be sure that your communication software, and prom and tty are all
set to the same 38400.

BUT! Most suns are set by default to 9600 in the prom, so until you
change the prom setting you'll have to use your serial console at 9600.
Myself, I always do the initial install on a clean hdd at 9600, and
boot once at that speed.  Only after I confirm that the install was
successful do I change the speed to 38400.  (Be alert when you change
the speed!  To change _from_ 9600 _to_ 38400, your serial console should
be at 9600.  On the _following_ boot, then your serial console needs to
be 38400.  Thus, before rebooting, also change your tty setting for the
serial a connection to 38400.  I have successfully changed /etc/ttys using
ed even when the baud rates didn't match, so it's not the end of the world
if you botch the install or forget to change something.)

HTH

henry