forwarding http requests with ipfw

[Robert Collins]

I've got a situation where I've got an internal host using a private 
ip/domainname. Let's say for the sake of this discussion the host is 
privatehost.internal.freebsd.org. privatehost isn't running a webserver. But 
I would like machines on the internal.freebsd.org network to query 
privatehost as if it was. When one of these machines queries privatehost I 
would like privatehost to forward those requests to my webserver, 
www.freebsd.org, so that it can handle the request. In order to accomplish 
that I have done the following:

My kernel was compiled with these options:
options         IPFIREWALL
options         IPFIREWALL_FORWARD
options         IPFIREWALL_FORWARD_EXTENDED


"ipfw list" looks like this:
00100 allow ip from any to any via lo0
00110 deny ip from any to 127.0.0.0/8
00120 deny ip from 127.0.0.0/8 to any
10000 fwd 216.136.204.117 tcp from any to me dst-port 80
65000 allow ip from any to any
65535 deny ip from any to any

The problem I am having is that it seems the packets never leave 
privatehost. tcpdump shows packets coming in destined for port 80. "ipfw 
show" shows that packets are matching my rule, but tcpdump never shows any 
packets going out to 216.136.204.117. tcpdump on 216.136.204.117  also shows 
that no packets are being recieved. I did a tcpdump on lo0 just for kicks, 
and that didn't show anything. It seems as if the packets are just 
disappearing. Someone on #freebsdhelp suggested doing a "sysctl -w 
net.inet.ip.forwarding=1" but that didn't help the situation. Is there 
something minor I'm missing here...or am I totally off in my understanding 
of how "ipfw fwd" works?

Thanks
-rcollins