Use NDC to log IP addresses

I was thinking about using Log4j's NDC (Nested Diagnostic Context) 
mechanism to allow output of the remote IP address in the logs. Attached 
to this email is a modified ApplicationGateway that seems to do the 
trick. As long as you have the %x pattern defined in your appender(s) 
you should be able to see the remote IP address on the logging 
statements in your code.

Jake/Christian: what do you think of this implementation? Is this the 
right spot for it? Search for saw_061203_1 to see what I added.

Any comments would be appreciated.

Thanks,
-shawn