> Dan had mentioned that ofwboot allowed some form of kernel debugging,
> but I cant seem  remember how exactly it worked.

If you pass "-d" as one of the boot args, it will drop into ddb as
soon as the kernel starts. But that's ddb, for local debugging, not
gdb.

NetBSD has remote gdb in the same way FreeBSD does, but the lack of a
simple serial port on the G3 means you're not going to be able to use
it.

-- Dan