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#	This file explain how to set Clement to handle E-mail
#	from the external world while nothing is changed to
#	the current SMTP daemon configuration.
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1. Principle:
   By default, Clement is listening on port 2525, you need to
   accept and redirect all external request to that port.
   To do so, you need to add rules to your current IPTABLES
   definitions.


2. iptables rules.

   Currently you have something like this to handle E-mail
   traffic.
   modprobe iptable_nat
   iptables -I INPUT -i eth0 -p tcp --dport smtp -j ACCEPT

   you need to add following rules
   iptables -I INPUT -i eth0 -p tcp --dport 2525 -j ACCEPT
   iptables -I PREROUTING -i eth0 -p tcp --dport smtp -j DNAT -t nat -- to <ip_on_eth0>:2525

   PREROUTING directive is to have all EXTERNAL smtp request redirected
   to port 2525.

   As an example if you are using /etc/sysconfig/iptables to store
   the firewall rule, add the following at the end of the file:

   *nat
   -A PREROUTING -i eth0 -p tcp --dport 25 -j DNAT --to IP.ON.ETH.0:2525
  COMMIT

2. Testing.
   To test if everything is working fine, 
	
   first, while being on the server itself, do from command line
   "telnet 'your_eth0_ip' 25"
   A prompt about your usual SMTP daemon should be returned (then type
   QUIT)
	
   second, while being on an external client, do from command line
   telnet 'your_eth0_ip' 25
   A prompt like:

   220 reverse_address ESMTP clement-2.0-XXX; Mon, 03 Oct 2005 14:47:52 -0400

   will be displayed (the type QUIT)

   This prove your standard SMTP daemon is still working while
   Clement is able to trap All external E-mail for diligent checking
   before dispatching them to standard SMTP daemon.
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