OK this is pretty easy.  

First your kernel has to be capable of doing serial console.  I'm using
2.2.19 and prefer to do a "make menuconfig" for my kernel configuration.

Under "character devices" be sure to have the following built-in (*)

	Virtual terminal
	Support for console on virtual terminal
	Standard/Generic dumb serial support
	Support for console on serial port

Full documents are found in the serial-console.txt
file in the kernel source under the "Documentation" directory.  I just added
these two lines to my lilo.conf before the line that reads "default=linux"

serial=0,9600n8
append="console=ttyS0,9600 console=tty0"

Where serial = ttyS0, 9600 baud, no parity and 8 data bits
In the append line I put console=ttyS0 and console=tty0 because I still want
tty0 to have console capabilities.

After this I uncomment this line in inittab so I can log in serially

T0:23:respawn:/sbin/getty -L ttyS0 9600 vt100

>From distro to distro the inittab might look a little different but this
should be enough to get you pointed in the right direction.

To get the box not to give me a keyboard error, I told it through the 
motherboard bios set up NOT to pause on keyboard errors.  I still have a
vga card in the box just in case it gets royally screwed.

Hope this helps ...

	Mike