Here the code, is very very simple:
<?php
$mbox = imap_open ('{imap.aol.com:993/imap/ssl}INBOX', 'user', 'pass' ) or die("can't connect: " . imap_last_error());
print_r($mbox);
?>
or (for gmail account)
<?php
$mbox = imap_open ('{imap.gmail.com:993/imap/ssl}INBOX', 'user', 'pass' ) or die("can't connect: " . imap_last_error());
print_r($mbox);
?>