Hi, I will elaborate my problem. I am looking for solution for following problem. I have A Linux interent gateway server having 3 NIC cards 1) eth0 connected to internet. 2) eth1 connected to private LAN (192.168.0.1.) 3) eth2 connected to DMZ server.(10.0.0.1) DMZ server is with one LAN card (eth0 : 10.0.0.2) On DMZ, DNS, Web and sendmail are installed. Iptables prerouting rules are set on Gateway server so that users from LAN 192.168.0.0 can acess web as well as mail server. Now I want to allow LAN users to send emails to each other on LAN but want to allow some LAN users to send email to Internet(Outside world). Is there any way using Linux iptables firewall to acieve this requirement. thanks for support. _______________________________ Do you Yahoo!? Express yourself with Y! Messenger! Free. Download now. http://messenger.yahoo.com