HOW TO FAKEMAIL

I'm new to this list and am sorry if this is a frequently asked question. Can someone tell me how "fakemail" works and how to do it. I need to send mail to the "ftp by mail" server at decwrl.dec.com and want the host to think that it is from another address. Basicly, I want to send it my ftp request from one e-mail address and have it mail what I'm requesting to a different one. The only way that I know of to do this is with fakemail. Any suggestions?