Interfacing JavaMail with sendmail...can it be done?

Im working on a site that uses the JavaMail API to send simple emails to its members when they sign up (usual stuff, username-password) The hosting company doesnt allow relaying which is really stupid seeing as how the mail comes from this site! Anyways, Ive seen the free email host posts & what not on this site but I had another idea. I have sendmail on this server & it works flawlessly......is there anyway anybody knows to communicate with sendmail from javamail... or even better can Javamail invoke cgiemail, which I also have on the server.....Any and all help in this would be much appreciated!