hi all I've got this network as sketched below... internal net | | +-----+----+ +--------+ | | | router +------+ Firewall |------ dmz +--------+ | | +----------+ The computers on the dmz and the internal net have all unofficial addresses with DNATing into the DMZ for those that should be available from the outside. The problem occurs when a computer on the dmz (192.168.x.y) tries to address another computer there by its official address (resolved from DNS). The firewall (netfilter/iptables) doesn't seem to be able to do the dmz -> netfilter -> dmz NATing. Any ideas? roy -- Roy Sigurd Karlsbakk, Datavaktmester ProntoTV AS - http://www.pronto.tv/ Tel: +47 9801 3356 Computers are like air conditioners. They stop working when you open Windows.