diff --git a/AbstractBrowser.php b/AbstractBrowser.php
index de85599f..dbd6051c 100644
--- a/AbstractBrowser.php
+++ b/AbstractBrowser.php
@@ -451,7 +451,7 @@ protected function doRequestInProcess($request)
         }
 
         if (!$process->isSuccessful() || !preg_match('/^O\:\d+\:/', $process->getOutput())) {
-            throw new \RuntimeException(sprintf('OUTPUT: %s ERROR OUTPUT: %s', $process->getOutput(), $process->getErrorOutput()));
+            throw new \RuntimeException(sprintf('OUTPUT: %s ERROR OUTPUT: %s.', $process->getOutput(), $process->getErrorOutput()));
         }
 
         return unserialize($process->getOutput());