Hidding SMTP info?

[Bob Tanner <tanner@real-time.com>]

Our network behind the firewall has grown to a point where we now have a
central mail server, which all client machines relay their email to. This
central server then works with the firewall to securely deliver the smtp
traffic to the Internet.

The problem is now there is a 'security' problem because sendmail stamps the
message at each hop, so our internal domain is being broadcast to the world.

For instance, you get

Received: (from tanner@localhost)
        by bobs.machine.real-time.com (8.10.2/8.10.2) id e587MZb06706;
        Thu, 8 Jun 2000 02:22:35 -0500

Here you can see that our internal domain is 'machine.real-time.com' and that
my computer's host name is 'bobs'.

Received: (from tanner@bobs.machine.real-time.com)
        by mailserver.machine.real-time.com (8.10.2/8.10.2) id e587MZb06706;
        Thu, 8 Jun 2000 02:22:35 -0500

Here you can see that our internal domain is 'machine.real-time.com' and that 
the central mail server is called mail server.

etc, etc, etc...

Anyone to protect this info?


-- 
Bob Tanner <tanner@real-time.com>       | Phone : (952)943-8700
http://www.mn-linux.org                 | Fax   : (952)943-8500
Key fingerprint =  6C E9 51 4F D5 3E 4C 66 62 A9 10 E5 35 85 39 D9