That's because automail.php is only used for remote piping, which sounds like not at all what you're trying to do.
See here for how to set up scheduling and POP/IMAP polling.
http://osticket.com/wiki/POP3/IMAP_Settings(http://osticket.com/wiki/POP3/IMAP_Settings)
If you really do want/need to set up remote piping, the instructions for that are here: http://osticket.com/wiki/Email_Piping(http://osticket.com/wiki/Email_Piping)