When using Icedove to send email, the computer's real IP address is disclosed to the SMTP relay, that usually writes it down to a `Received:` header inside outgoing email. This private information is therefore disclosed to:
When using a NAT-ed Internet connection, the disclosed IP is a local network one (e.g. 192.168.1.42), which usually does not reveal too much. On the other hand, when connecting directly to the Internet, e.g. using a PPP or DSL modem and no router, the disclosed IP truly reveals the location of the amnesia user.