title: Joomla - Argument 4 passed to JPluginHelper::importPlugin()
body: <p>I'm trying to update my Joomla installation from 2.5.28 to 3.3.6 but I get a blank screen. There's an error in my error_log file stating "PHP Catchable fatal error:  Argument 4 passed to JPluginHelper::importPlugin() must be an instance of JEventDispatcher"... Any ideas will be helpful, thanks!</p>