@@ -313,7 +313,7 @@ private function handleRequest(TransportInterface $transport, Request $request,
             } catch (\Throwable $e) {
                 $this->logger->error(\sprintf('Uncaught exception: %s', $e->getMessage()), ['exception' => $e]);
 
-                $error = Error::forInternalError($e->getMessage(), $request->getId());
+                $error = Error::forInternalError(self::INTERNAL_ERROR_MESSAGE, $request->getId());
                 $errorEvent = $this->dispatchEvent(new ErrorEvent($error, $request, $session, $e));
                 $error = $errorEvent->getError();
 
 
@@ -670,7 +670,8 @@ public function testHandlerUnexpectedExceptionReturnsInternalError(): void
         $message = json_decode($outgoing[0]['message'], true);
         $this->assertArrayHasKey('error', $message);
         $this->assertEquals(Error::INTERNAL_ERROR, $message['error']['code']);
-        $this->assertStringContainsString('Unexpected error', $message['error']['message']);
+        $this->assertSame('Internal server error.', $message['error']['message']);
+        $this->assertStringNotContainsString('Unexpected error', $message['error']['message']);
     }
 
     #[TestDox('Notification handler exceptions are caught and logged')]
Original file line number	Diff line number	Diff line change
@@ -670,7 +670,8 @@ public function testHandlerUnexpectedExceptionReturnsInternalError(): void
670	670	$message = json_decode($outgoing[0]['message'], true);
671	671	$this->assertArrayHasKey('error', $message);
672	672	$this->assertEquals(Error::INTERNAL_ERROR, $message['error']['code']);
673		- $this->assertStringContainsString('Unexpected error', $message['error']['message']);
	673	+ $this->assertSame('Internal server error.', $message['error']['message']);
	674	+ $this->assertStringNotContainsString('Unexpected error', $message['error']['message']);
674	675	}
675	676
676	677	#[TestDox('Notification handler exceptions are caught and logged')]