diff --git a/extensions/swiftmailer/Mailer.php b/extensions/swiftmailer/Mailer.php
index 58f0f23..c00fad6 100644
--- a/extensions/swiftmailer/Mailer.php
+++ b/extensions/swiftmailer/Mailer.php
@@ -145,7 +145,7 @@ class Mailer extends BaseMailer
 					$transport->$name = $value;
 				} else {
 					$setter = 'set' . $name;
-					if (method_exists($transport, $setter)) {
+					if (method_exists($transport, $setter) || method_exists($transport, '__call')) {
 						$transport->$setter($value);
 					} else {
 						throw new InvalidConfigException('Setting unknown property: ' . get_class($transport) . '::' . $name);
diff --git a/tests/unit/extensions/swiftmailer/MailerTest.php b/tests/unit/extensions/swiftmailer/MailerTest.php
index 306e128..24602b2 100644
--- a/tests/unit/extensions/swiftmailer/MailerTest.php
+++ b/tests/unit/extensions/swiftmailer/MailerTest.php
@@ -53,6 +53,8 @@ class MailerTest extends VendorTestCase
 		$transportConfig = [
 			'class' => 'Swift_SmtpTransport',
 			'host' => 'localhost',
+			'username' => 'username',
+			'password' => 'password',
 		];
 		$mailer->setTransport($transportConfig);
 		$transport = $mailer->getTransport();
diff --git a/tests/unit/extensions/swiftmailer/MessageTest.php b/tests/unit/extensions/swiftmailer/MessageTest.php
index fdecd88..c46b43d 100644
--- a/tests/unit/extensions/swiftmailer/MessageTest.php
+++ b/tests/unit/extensions/swiftmailer/MessageTest.php
@@ -119,6 +119,8 @@ class MessageTest extends VendorTestCase
 	{
 		$charset = 'utf-16';
 		$subject = 'Test Subject';
+		$from = 'from@somedomain.com';
+		$replyTo = 'reply-to@somedomain.com';
 		$to = 'someuser@somedomain.com';
 		$cc = 'ccuser@somedomain.com';
 		$bcc = 'bccuser@somedomain.com';
@@ -126,6 +128,8 @@ class MessageTest extends VendorTestCase
 		$messageString = $this->createTestMessage()
 			->setCharset($charset)
 			->setSubject($subject)
+			->setFrom($from)
+			->setReplyTo($replyTo)
 			->setTo($to)
 			->setCc($cc)
 			->setBcc($bcc)
@@ -133,6 +137,8 @@ class MessageTest extends VendorTestCase
 
 		$this->assertContains('charset=' . $charset, $messageString, 'Incorrect charset!');
 		$this->assertContains('Subject: ' . $subject, $messageString, 'Incorrect "Subject" header!');
+		$this->assertContains('From: ' . $from, $messageString, 'Incorrect "From" header!');
+		$this->assertContains('Reply-To: ' . $replyTo, $messageString, 'Incorrect "Reply-To" header!');
 		$this->assertContains('To: ' . $to, $messageString, 'Incorrect "To" header!');
 		$this->assertContains('Cc: ' . $cc, $messageString, 'Incorrect "Cc" header!');
 		$this->assertContains('Bcc: ' . $bcc, $messageString, 'Incorrect "Bcc" header!');
@@ -141,19 +147,6 @@ class MessageTest extends VendorTestCase
 	/**
 	 * @depends testGetSwiftMessage
 	 */
-	public function testSetupFrom()
-	{
-		$from = 'someuser@somedomain.com';
-		$messageString = $this->createTestMessage()
-			->setFrom($from)
-			->toString();
-		$this->assertContains('From: ' . $from, $messageString, 'Incorrect "From" header!');
-		$this->assertContains('Reply-To: ' . $from, $messageString, 'Incorrect "Reply-To" header!');
-	}
-
-	/**
-	 * @depends testGetSwiftMessage
-	 */
 	public function testSend()
 	{
 		$message = $this->createTestMessage();