Edit include/mail.inc, add my own SMTP setting there - drupal

Question

The following function is contained in include/mail.inc of Drupal6, it uses the default SMTP settings buried in a file named "php.ini" to send mail.
function drupal_mail_send($message) {
// Allow for a custom mail backend.
if (variable_get('smtp_library', '') && file_exists(variable_get('smtp_library', ''))) {
include_once './'. variable_get('smtp_library', '');
return drupal_mail_wrapper($message);
}
else {
$mimeheaders = array();
foreach ($message['headers'] as $name => $value) {
$mimeheaders[] = $name .': '. mime_header_encode($value);
}
return mail(
$message['to'],
mime_header_encode($message['subject']),
// Note: e-mail uses CRLF for line-endings, but PHP's API requires LF.
// They will appear correctly in the actual e-mail that is sent.
str_replace("\r", '', $message['body']),
// For headers, PHP's API suggests that we use CRLF normally,
// but some MTAs incorrecly replace LF with CRLF. See #234403.
join("\n", $mimeheaders)
);
}
}
but I use shared host, therefore i can't edit php.ini, i want to edit the above function "drupal_mail_send", add the codes below into that function so that it can bypass the PHP mail() function and send email directly to my favorite SMTP server.
include('Mail.php');
$recipients = array( 'someone#example.com' ); # Can be one or more emails
$headers = array (
'From' => 'someone#example.com',
'To' => join(', ', $recipients),
'Subject' => 'Testing email from project web',
);
$body = "This was sent via php from project web!\n";
$mail_object =& Mail::factory('smtp',
array(
'host' => 'prwebmail',
'auth' => true,
'username' => 'YOUR_PROJECT_NAME',
'password' => 'PASSWORD', # As set on your project's config page
#'debug' => true, # uncomment to enable debugging
));
$mail_object->send($recipients, $headers, $body);
Could you write down the modified code for my reference?

Answer 1

The code in drupal_mail_send is part o the Drupal core functionality and should not be changed directly as your changes may be overwritten when you update Drupal.
Modifications of Drupal core files is often referred to by the Drupal community as "hacking core" and is largely discouraged.
Drupal already has a number of modules available which may help you. See:
http://drupal.org/project/phpmailer module:
Adds SMTP support for sending e-mails using the PHPMailer library.
Comes with detailed configuration instructions for how to use Google
Mail as mail server.
http://drupal.org/project/smtp module:
This module allows Drupal to bypass the PHP mail() function and send
email directly to an SMTP server.