Goodness, what am I doing wrong?  Here is how my LAN is set up:

"inside" network on LAN port: 192.168.15.0/24
LAN port IP address: 192.168.15.1 (also providing DHCP to my inside 
clients)
"outside" network on WAN port: DHCP (from TimeWarner RoadRunner)

I can plug in the m0n0wall to the LAN switch, plug the WAN ether into 
the WAN port, boot up m0n0wall and everything looks good.  I get a DHCP 
address from m0n0, and the WAN interface gets a DHCP address from 
RoadRunner (and registers that IP address with dyndns - that's a cool 
feature).

So all looks good.

Here's what isn't working: outbound packets from my clients on 
192.168.15.0/24 to the Internet.

I stripped out all LAN firewall rules to attempt to allow all traffic 
from the LAN port to the world.  My single rule now looks like:

LAN Interfaces:
Proto	Source	Port	Destination	Port	Description
*		LAN Net	*	*			*	default LAN -> ANY

My WAN rules are as follows:
Proto	Source	Port	Destination	Port	Destination	
*		LAN net	*	*			*	Allow outgoing packets from LAN interface

My Outbound NAT rules are as follows:
Interface	Source			Destination	Target	Description
WAN	192.168.15.50/24	*			*		General outbound NAT rule


NOTE:  I've tried having NO WAN rule as well as having the above WAN 
rule and I get the same results: my clients on 192.168.15.0/24 cannot 
communicate to the Internet.

The INSANE thing is I can get *INBOUND* nat to work (i.e. mapping my 
WAN DHCP address to internal 192.168.15.0/24 hosts for various 
protocols) but I cannot get my laptop, running Mac OS 10.2.8, to get 
out on the Internet.  Each time I try to access a web host I get an 
error "server cannot be reached" or some such thing.  I also tested 
this from my command line on my Mac by trying a 'wget 
http://www.roadsideamerica.com/index.html' which didn't work either.

Any thoughts?  Where am I going wrong?

Greg