sawtooth: no carrier on gem0

[Ben Rosengart]

Hello good people,
  I am experimenting with FreeBSD-ppc for the first time.  The install
went well, but I cannot seem to get the ethernet working.  ifconfig(8)
reports that gem0 has "no carrier" and that the media type is set to
"autodetect (none)".  This is the only ethernet interface, so I assume
it's the right one to get to the on-board ethernet hardware.  This
interface works just fine under Mac OS X, so it does not appear to be
a hardware problem.  The machine is a dual 450-MHz G4, i.e. this one:

  http://www.lowendmac.com/ppc/g4saw.shtml

The wiki page does not say anything about this problem, though it
refers to the "outdated official project page", which says:

  On-board BMAC+ ethernet does not work. There is a work-in-progress
  bm(4) driver available on Peter Grehan's personal page here (see
  if_bm.c and if_bmreg.h).

However, I seem to be using gem(4), not bm(4).

Advice would be greatly appreciated.

Thanks in advance,

-- 
 Ben Rosengart                                          ben at narcissus.net
       "Young people should be seen and not heard, because they're
        good-looking but not too bright.  We're pretty bright now,
        but we're ugly." -- Grace Slick on the '60s youth movement