diff --git a/phpBB/phpbb/message/message.php b/phpBB/phpbb/message/message.php
index b1d95cf5b8..ea6da8419a 100644
--- a/phpBB/phpbb/message/message.php
+++ b/phpBB/phpbb/message/message.php
@@ -263,15 +263,19 @@ class message
 					$messenger_method->set_addresses($recipient);
 					$messenger_method->reply_to($this->sender_address);
 
-					$messenger_method->header('X-AntiAbuse', 'Board servername - ' . $this->server_name);
-					$messenger_method->header('X-AntiAbuse', 'User IP - ' . $this->sender_ip);
-					if ($this->sender_id)
+					if (isset($messenger_method->headers) && $messenger_method->headers instanceof \Symfony\Component\Mime\Header\Headers)
 					{
-						$messenger_method->header('X-AntiAbuse', 'User_id - ' . $this->sender_id);
-					}
-					if ($this->sender_username)
-					{
-						$messenger_method->header('X-AntiAbuse', 'Username - ' . $this->sender_username);
+						$messenger_method->headers->addHeader('X-AntiAbuse', 'Board servername - ' . $this->server_name);
+						$messenger_method->headers->addHeader('X-AntiAbuse', 'User IP - ' . $this->sender_ip);
+						if ($this->sender_id)
+						{
+							$messenger_method->headers->addHeader('X-AntiAbuse', 'User_id - ' . $this->sender_id);
+						}
+
+						if ($this->sender_username)
+						{
+							$messenger_method->headers->addHeader('X-AntiAbuse', 'Username - ' . $this->sender_username);
+						}
 					}
 
 					$messenger_method->subject(html_entity_decode($this->subject, ENT_COMPAT));
diff --git a/phpBB/phpbb/messenger/method/email.php b/phpBB/phpbb/messenger/method/email.php
index adf0951fec..78059174b3 100644
--- a/phpBB/phpbb/messenger/method/email.php
+++ b/phpBB/phpbb/messenger/method/email.php
@@ -47,7 +47,7 @@ class email extends base
 	protected $from;
 
 	/** @var Headers */
-	protected $headers;
+	public $headers;
 
 	/**
 	 * @var int