Index: wp-includes/class-smtp.php
===================================================================
--- wp-includes/class-smtp.php	(revision 39941)
+++ wp-includes/class-smtp.php	(working copy)
@@ -378,7 +378,7 @@
      * @see hello()
      * @param string $username The user name
      * @param string $password The password
-     * @param string $authtype The auth type (PLAIN, LOGIN, CRAM-MD5)
+     * @param string $authtype The auth type (PLAIN, LOGIN, NTLM, CRAM-MD5, XOAUTH2)
      * @param string $realm The auth realm for NTLM
      * @param string $workstation The auth workstation for NTLM
      * @param null|OAuth $OAuth An optional OAuth instance (@see PHPMailerOAuth)
@@ -414,7 +414,7 @@
             );
 
             if (empty($authtype)) {
-                foreach (array('CRAM-MD5', 'LOGIN', 'PLAIN') as $method) {
+                foreach (array('CRAM-MD5', 'LOGIN', 'PLAIN', 'NTLM', 'XOAUTH2') as $method) {
                     if (in_array($method, $this->server_caps['AUTH'])) {
                         $authtype = $method;
                         break;
@@ -462,6 +462,69 @@
                     return false;
                 }
                 break;
+            case 'XOAUTH2':
+                //If the OAuth Instance is not set. Can be a case when PHPMailer is used
+                //instead of PHPMailerOAuth
+                if (is_null($OAuth)) {
+                    return false;
+                }
+                $oauth = $OAuth->getOauth64();
+
+                // Start authentication
+                if (!$this->sendCommand('AUTH', 'AUTH XOAUTH2 ' . $oauth, 235)) {
+                    return false;
+                }
+                break;
+            case 'NTLM':
+                /*
+                 * ntlm_sasl_client.php
+                 * Bundled with Permission
+                 *
+                 * How to telnet in windows:
+                 * http://technet.microsoft.com/en-us/library/aa995718%28EXCHG.65%29.aspx
+                 * PROTOCOL Docs http://curl.haxx.se/rfc/ntlm.html#ntlmSmtpAuthentication
+                 */
+                require_once 'extras/ntlm_sasl_client.php';
+                $temp = new stdClass;
+                $ntlm_client = new ntlm_sasl_client_class;
+                //Check that functions are available
+                if (!$ntlm_client->initialize($temp)) {
+                    $this->setError($temp->error);
+                    $this->edebug(
+                        'You need to enable some modules in your php.ini file: '
+                        . $this->error['error'],
+                        self::DEBUG_CLIENT
+                    );
+                    return false;
+                }
+                //msg1
+                $msg1 = $ntlm_client->typeMsg1($realm, $workstation); //msg1
+
+                if (!$this->sendCommand(
+                    'AUTH NTLM',
+                    'AUTH NTLM ' . base64_encode($msg1),
+                    334
+                )
+                ) {
+                    return false;
+                }
+                //Though 0 based, there is a white space after the 3 digit number
+                //msg2
+                $challenge = substr($this->last_reply, 3);
+                $challenge = base64_decode($challenge);
+                $ntlm_res = $ntlm_client->NTLMResponse(
+                    substr($challenge, 24, 8),
+                    $password
+                );
+                //msg3
+                $msg3 = $ntlm_client->typeMsg3(
+                    $ntlm_res,
+                    $username,
+                    $realm,
+                    $workstation
+                );
+                // send encoded username
+                return $this->sendCommand('Username', base64_encode($msg3), 235);
             case 'CRAM-MD5':
                 // Start authentication
                 if (!$this->sendCommand('AUTH CRAM-MD5', 'AUTH CRAM-MD5', 334)) {
@@ -1183,4 +1246,4 @@
 
 		return false;
     }
-}
+}
\ No newline at end of file
Index: wp-includes/class-phpmailer.php
===================================================================
--- wp-includes/class-phpmailer.php	(revision 39941)
+++ wp-includes/class-phpmailer.php	(working copy)
@@ -288,7 +288,7 @@
 
     /**
      * SMTP auth type.
-     * Options are CRAM-MD5, LOGIN, PLAIN, attempted in that order if not specified
+     * Options are CRAM-MD5, LOGIN, PLAIN, NTLM, XOAUTH2, attempted in that order if not specified
      * @var string
      */
     public $AuthType = '';
@@ -1517,7 +1517,6 @@
     public function getSMTPInstance()
     {
         if (!is_object($this->smtp)) {
-			require_once( 'class-smtp.php' );
             $this->smtp = new SMTP;
         }
         return $this->smtp;
@@ -4037,4 +4036,4 @@
         $errorMsg = '<strong>' . $this->getMessage() . "</strong><br />\n";
         return $errorMsg;
     }
-}
+}
\ No newline at end of file