Hello all,
when internal clients that work with Linux or outlool express uses our Exchange 5.5 IMC to relay messages to the Internet, the internal IP of the client is shown in the headers (received: XX....).

I´m running exchange 5.5 SP4 over w2000 updated. This server is in a DMZ (2 network adapters) behind a firewall. The "routing restrictions" of the IMC is set to "Host & clients with these IP addresses"
How can I avoid these? Is there a way to masquerade these IPs?
Thanks.