Dumping a panic during boot kernel over firewire

[Thomas Lippert]

Hi all,
What is the procedure for dumping a kernel over firewire. Maybe i am being dense, but i can't find the  "kern.firewire.fwmem_node=[node_id]" in sysctl. Trying to set it gives me a " sysctl: unknown oid 'kern.firewire.fwmem_node' " message.
output of uname -a is 
"FreeBSD ovid.dhcppc5 4.9-RELEASE FreeBSD 4.9-RELEASE #5: Wed Nov 19 19:12:21 PST 2003     clippert at ovid.dhcppc5:/usr/src/sys/compile/OVID  i386"

I am hoping to someday figure out or at least provide the output for why it is that this laptop crashes early in boot on my laptop.
Searching the mail list archives and googling have turned up no leads other than to say that it is possible. 
     Thanks in advance,
               -Thomas