Error when send email

[deekito]

Hi everybody,

I have a problem when config the Mantis email function. Here is my configuration:

$g_phpMailer_method = PHPMAILER_METHOD_SMTP; # or PHPMAILER_METHOD_SMTP, PHPMAILER_METHOD_SENDMAIL
$g_smtp_host = 'smtp.exmail.qq.com'; # used with PHPMAILER_METHOD_SMTP
$g_smtp_username = 'username'; # used with PHPMAILER_METHOD_SMTP
$g_smtp_password = 'password'; # used with PHPMAILER_METHOD_SMTP
$g_administrator_email = 'administrator@example.com';
$g_webmaster_email = 'webmaster@example.com';
$g_from_email = 'noreply@example.com'; # the "From: " field in emails
$g_return_path_email = 'admin@example.com'; # the return address for bounced mail
$g_smtp_port = 465;
$g_smtp_connection_mode = 'ssl';
$g_log_level = LOG_EMAIL | LOG_EMAIL_RECIPIENT;
$g_log_destination = 'file:/tmp/mantisbt.log';

When i test the email function, the log file records the error info like this:
2015-10-21 16:48 CST mail Sending message #1 queued on 2015-10-21 16:26 CST
2015-10-21 16:48 CST mail ERROR: Message could not be sent - SMTP Error: Could not connect to SMTP host.
2015-10-21 16:48 CST mail Sending message #2 queued on 2015-10-21 16:26 CST
2015-10-21 16:48 CST mail ERROR: Message could not be sent - SMTP Error: Could not connect to SMTP host.
2015-10-21 16:48 CST mail Sending message #3 queued on 2015-10-21 16:28 CST
2015-10-21 16:48 CST mail ERROR: Message could not be sent - SMTP Error: Could not connect to SMTP host.
2015-10-21 16:48 CST mail Sending message #4 queued on 2015-10-21 16:44 CST
2015-10-21 16:48 CST mail ERROR: Message could not be sent - SMTP Error: Could not connect to SMTP host.
2015-10-21 16:48 CST mail Sending message #5 queued on 2015-10-21 16:44 CST
2015-10-21 16:48 CST mail ERROR: Message could not be sent - SMTP Error: Could not connect to SMTP host.
2015-10-21 16:48 CST mail Sending message #6 queued on 2015-10-21 16:48 CST
2015-10-21 16:48 CST mail ERROR: Message could not be sent - SMTP Error: Could not connect to SMTP host.

What have i missed?