carlosrevilla: I changed the bottom bit, so..

alias -l mailopen {
inc %mail.retry | unset %mcommand
echo 3 -a Attempting $+(smtp.tiscali.couk:25)
.sockclose mail | sockopen mail $+(smtp.tiscali.co.uk 25)
sockmark mail $1-
}

Which worked for me, so try finding out your ISPs smtp server and putting it there