Talk:Replace IP address with name in headers

If you are using a version of Thunderbird before 2.0.0.24 and your PC is behind a NAT box or a router it may send your PC's IP address instead of a "fully qualified domain name" (FQDN) in its reply. - I don't think this entirely correct. While there have been various small changes between versions, 3.x doesn't behave significantly different than 2.0 with respect to the greeting argument. The algorithm to determine a FQDN as the host name is trivial: If it contains a dot (.), it's considered a FQDN, otherwise not. That's the reason why many Linux systems provide their host name as registered with DNS for the greeting, which usually is a "true" FQDN and hence contains a dot. On Windows, the host name as entered is used, which the OS won't allow to add a period, thus the local IP address is always used, regardless of whether or not you are behind a modem or router with NAT or connected directly. Mac OSX host names can contain a dot, thus it depends on what the user or administrator entered if the name or the IP address is used. See bug 425652 for further discussion. --Rsx11m 01:51, 16 September 2010 (UTC)