resource imap_open ( string $mailbox , string $username , string $password [, int $options = NIL [, int $n_retries = 0 [, array $params = NULL ]]] )
Opens an IMAP stream to a mailbox. This function can also be used to open streams to POP3 and NNTP servers, but some functions and features are only available on IMAP servers.
Returns an IMAP stream on success or FALSE on error.