Can't sshd into 5.0

Dear FreeBSD,

     This is an old problem that I still have.  I have more data on it. It
is not just ssh (see my point 6. below), so kind advice before about sshd
pertained to a red herring (thank you anyway).  To summarize:

1.  Box = new, hardly-used-because-of-this-problem 5.0 FreeBSD system,
which is a Dell 2350 with an added ethernet card.  Was rl0.  Now
I have a new bge0 to try; no improvement.  

2.  Gateway = a FreeBSD 4.7 running natd, connected to DSL.  Local
network alias is 192.168.0.3.

3.  IP of 5.0 system is 192.168.0.12

4.  5.0 system can ssh to gateway machine (I am typing on it now), but it
cannot ping or ssh directly to any place outside of 192.168...
I believe the cards and wires must be working, or I could not conduct
an ssh connection to the gateway.  

5.  My laptop, whether it is running FreeBSD or Window98, is on the
192.168 network, as is an XP system, and they are all using the gateway
(which is running natd) just fine, and have been for more than a year.

6.  Most strangely and simply, I cannot, from the gateway FreeBSD 4.7
system, telnet, ping, nor ssh into the 5.0 system.  This happens even
though I am logged on from the 5.0 system!  I can telnet and ssh to myself
(localhost) on the 5.0 system.

     Can anyone think of something for me to try or probe?  

     Since I don't have any much data on this machine, I think I will
install 4.8 over it and see how that works.  Too bad; I wanted to be in
the future.

-- 
Wayne M Barnes
wayne_at_etaq.com    fax: (314) 754-9556