diff --git a/Tests/Transport/Serialization/PhpSerializerTest.php b/Tests/Transport/Serialization/PhpSerializerTest.php
index c83606a..7ff0a00 100644
--- a/Tests/Transport/Serialization/PhpSerializerTest.php
+++ b/Tests/Transport/Serialization/PhpSerializerTest.php
@@ -33,21 +33,21 @@ public function testEncodedIsDecodable()
 
     public function testDecodingFailsWithMissingBodyKey()
     {
+        $serializer = $this->createPhpSerializer();
+
         $this->expectException(MessageDecodingFailedException::class);
         $this->expectExceptionMessage('Encoded envelope should have at least a "body", or maybe you should implement your own serializer');
 
-        $serializer = $this->createPhpSerializer();
-
         $serializer->decode([]);
     }
 
     public function testDecodingFailsWithBadFormat()
     {
+        $serializer = $this->createPhpSerializer();
+
         $this->expectException(MessageDecodingFailedException::class);
         $this->expectExceptionMessageMatches('/Could not decode/');
 
-        $serializer = $this->createPhpSerializer();
-
         $serializer->decode([
             'body' => '{"message": "bar"}',
         ]);
@@ -55,11 +55,11 @@ public function testDecodingFailsWithBadFormat()
 
     public function testDecodingFailsWithBadBase64Body()
     {
+        $serializer = $this->createPhpSerializer();
+
         $this->expectException(MessageDecodingFailedException::class);
         $this->expectExceptionMessageMatches('/Could not decode/');
 
-        $serializer = $this->createPhpSerializer();
-
         $serializer->decode([
             'body' => 'x',
         ]);
@@ -67,16 +67,29 @@ public function testDecodingFailsWithBadBase64Body()
 
     public function testDecodingFailsWithBadClass()
     {
+        $serializer = $this->createPhpSerializer();
+
         $this->expectException(MessageDecodingFailedException::class);
         $this->expectExceptionMessageMatches('/class "ReceivedSt0mp" not found/');
 
-        $serializer = $this->createPhpSerializer();
-
         $serializer->decode([
             'body' => 'O:13:"ReceivedSt0mp":0:{}',
         ]);
     }
 
+    public function testDecodingFailsForPropertyTypeMismatch()
+    {
+        $serializer = $this->createPhpSerializer();
+        $encodedEnvelope = $serializer->encode(new Envelope(new DummyMessage('true')));
+        // Simulate a change of property type in the code base
+        $encodedEnvelope['body'] = str_replace('s:4:\"true\"', 'b:1', $encodedEnvelope['body']);
+
+        $this->expectException(MessageDecodingFailedException::class);
+        $this->expectExceptionMessageMatches('/Could not decode/');
+
+        $serializer->decode($encodedEnvelope);
+    }
+
     public function testEncodedSkipsNonEncodeableStamps()
     {
         $serializer = $this->createPhpSerializer();
diff --git a/Transport/Serialization/PhpSerializer.php b/Transport/Serialization/PhpSerializer.php
index b1cb42d..f9cd992 100644
--- a/Transport/Serialization/PhpSerializer.php
+++ b/Transport/Serialization/PhpSerializer.php
@@ -75,16 +75,14 @@ private function safelyUnserialize(string $contents): Envelope
             throw new MessageDecodingFailedException('Could not decode an empty message using PHP serialization.');
         }
 
-        $signalingException = new MessageDecodingFailedException(sprintf('Could not decode message using PHP serialization: %s.', $contents));
-
         if ($this->acceptPhpIncompleteClass) {
             $prevUnserializeHandler = ini_set('unserialize_callback_func', null);
         } else {
             $prevUnserializeHandler = ini_set('unserialize_callback_func', self::class.'::handleUnserializeCallback');
         }
-        $prevErrorHandler = set_error_handler(function ($type, $msg, $file, $line, $context = []) use (&$prevErrorHandler, $signalingException) {
+        $prevErrorHandler = set_error_handler(function ($type, $msg, $file, $line, $context = []) use (&$prevErrorHandler) {
             if (__FILE__ === $file) {
-                throw $signalingException;
+                throw new \ErrorException($msg, 0, $type, $file, $line);
             }
 
             return $prevErrorHandler ? $prevErrorHandler($type, $msg, $file, $line, $context) : false;
@@ -93,13 +91,19 @@ private function safelyUnserialize(string $contents): Envelope
         try {
             /** @var Envelope */
             $envelope = unserialize($contents);
+        } catch (\Throwable $e) {
+            if ($e instanceof MessageDecodingFailedException) {
+                throw $e;
+            }
+
+            throw new MessageDecodingFailedException('Could not decode Envelope: '.$e->getMessage(), 0, $e);
         } finally {
             restore_error_handler();
             ini_set('unserialize_callback_func', $prevUnserializeHandler);
         }
 
         if (!$envelope instanceof Envelope) {
-            throw $signalingException;
+            throw new MessageDecodingFailedException('Could not decode message into an Envelope.');
         }
 
         if ($envelope->getMessage() instanceof \__PHP_Incomplete_Class) {