Hi,
I'm soon to be moving web/mail/ftp to a new server, and while the DNS 
changes for my various domains are propagating around the internet I was 
wanting to transparently redirect those services from my old machine to 
the new one (both of which are real world servers, not on a local network).
I've tried several examples including [1], but don't seem to be able to 
get any to work. I have got ipv4_forwarding enabled.
I have, however, found a small C utility called redirect [2], which I 
can use if I can't get the iptables working correctly.
I'm at a bit of a loss as to what to try next. Any suggestions greatly 
appreciated.
Cheers,
Tom
[1] The best example I found was this one.
http://www.faqs.org/docs/Linux-mini/TransparentProxy.html
[2] 
http://sammy.net/~sammy/hacks/