Drupal: Edit email template from contact form

When submitting a message in my site-wide contact form in Drupal 6.x I get the following message along the top of every message:

[Name] sent a message us开发者_JS百科ing the contact form at [www.mysite.com/contact]

I would like to remove this message. Looking around, I've found it comes from the contact.module here:

$message['body'][] = t("!name sent a message using the contact form at !form.", array('!name' => $params['name'], '!form' => url($_GET['q'], array('absolute' => TRUE, 'language' => $language))), $language->language);

I've done a bit of research and it seems that I need to create a custom module with a hook_mail_alter() function to edit the contact.module. When it comes to this I get a bit lost. Could anyone kindly take me through the steps to accomplish the task?

Many thanks.

I did something like that recently. Here is a template you can use to get what you need. Most is from the contact module. The code below is from Drupal 7 but should work as is in Drupal 6.

/**
 * Implementation of hook_mail_alter().
 */
function modulename_mail_alter(&$message) {
  if ($message['id'] == 'contact_page_mail') {
    $language = $message['language'];
    $params = $message['params'];
    $variables = array(
      '!form-url' => url($_GET['q'], array('absolute' => TRUE, 'language' => $language)),
      '!sender-name' => format_username($params['sender']),
      '!sender-url' => $params['sender']->uid ? url('user/' . $params['sender']->uid, array('absolute' => TRUE, 'language' => $language)) : $params['sender']->mail,
    );
    $message['body'] = array();
    $message['body'][] = t("Your custom message with variables", $variables, array('langcode' => $language->language));
    $message['body'][] = $params['message']; // Append the user's message/
  }
}

function theme_mail_alter(&$message) {
  // only alter contact forms
  if (!empty($message['id']) && $message['id'] == 'contact_page_mail') {

    $contact_message = $message['params']['contact_message'];

    $message['body'] = [];

    $fields = $contact_message->getFields();
   
    $new_body .= 'Message:' . PHP_EOL . $contact_message->get('message')->value . PHP_EOL . PHP_EOL;

    foreach ($fields as $field_name => $field) {
        if (get_class($field->getFieldDefinition()) == 'Drupal\field\Entity\FieldConfig') {

            $new_body .= $field->getFieldDefinition()->label() . ':' . PHP_EOL;

            if (isset($contact_message->get($field_name)->entity->uri->value)) {
              $uri = $contact_message->get($field_name)->entity->uri->value;
              $url = file_create_url($uri);
              $new_body .=  $url . PHP_EOL . PHP_EOL;

            } else {
              $new_body .= $contact_message->get($field_name)->value . PHP_EOL . PHP_EOL;
            }

        }
    }

    $message['body'][] = $new_body;

  }
}