port forwarding problem

[<oarojo@intermediacorp.com>]

hello guys!!! Can someone help me on my problem regarding iptables???

This has been my problem a month now.. I'm running a redhat 7.3 firewall
server with two NICs; eth0 facing the internal network (192.168.0.x) and
eth1 facing the internet (external network). Now I wish to forward all
traffic on eth1, port 25 to another to my mail server (say, 192.168.0.2). I
did something like:

iptables -t nat -A POSTROUTING -s 192.168.0.0/24 -j MASQUERADE
iptables -A FORWARD -p tcp --dport 25 -d 192.168.0.2 -j ACCEPT
iptables -A PREROUTING -t nat -p tcp --dport 25 -d x.x.x.x -j DNAT
 --to 192.168.0.2

Now when i used to test SMTP connection thru telnetting from another
server... say:

#telnet xxx.xxx.xxx.xxx 25

It just stucked in there doesn't continue...

using nmap on my firewall:

#nmap xxx.xxx.xxx.xxx -p 25

it says that port 25 is filtered...


Is there anything wrong with my iptable rules? I would really appreciate if
you can send me your help... thanks!


Oliver