ANSWER:

Not sure if I correctly understand your ‘include your ip address when sending out emails’ but if you mean that IP address is being included to your mail message you could send email to yourself (on same or another email account belonging to you) and see message source (most clients give you this ability). There you should see all mail headers (including service ones like determining path of SMTP servers that mail traveled to get in to your inbox) – check if there is originating IP of sender in your case.

by Vadym S. Khondar from http://serverfault.com/questions/382756