smtp/pop and NAT only

[varun_saa@xxxxxxxx]

Hello,
     My server is on FC3 (fedora3)
eth0 is WAN ---> DSL router ----> ISP
eth1 is LAN

I would like to that 2 client 192.168.0.253
and 192.168.0.248 are connected to " fedora3 server "
via NAT.

And all other clients connected to "fedora3 server"
are able to only send / recieve mail.

Howto do that

Thanks

Varun