--- libraries/Error.class.php.orig	2011-11-13 18:40:23.860385540 +0100
+++ libraries/Error.class.php	2011-11-13 18:42:40.538840132 +0100
@@ -175,7 +175,7 @@
                 $this->getMessage() .
                 $this->getFile() .
                 $this->getLine() .
-                $this->getBacktrace()
+                serialize($this->getBacktrace())
             );
         }