Oops!  I have to apologize to anyone who tried to use my instructions
for setting up TCP/IP.  I made an error in these instructions, which
was also present and causing problems in my machine.  This error is in
the hostname.ae0 file:

> /etc/hostname.ae0:
> inet <insert your IP address or hostname here>
> dest <insert your router or gateway here>

This is incorrect.  The format of /etc/hostname.ae0 should be:
inet <insert your IP address here>

only.  Leave out the "dest..." line.  Thanks to Scott Reynolds for
correcting this mistake.  That's what I get for trying to give
instructions when I don't know what I'm doing, I guess!

Oh- if Johan Claesson is still following this thread, I did find
another clue you might want to check out if you haven't already gotten
this far.  To get your Mac to serve as a router, one thing you might
have to do is compile your own kernel with the "GATEWAY" option
enabled, to allow IP packet forwarding.  The kernel compiling FAQ is
at http://is.rice.edu/~ender/tmp/HOWTO/kernel.html.  Good luck!

-Jesse