In the error log appear this:
[Thu Apr 17 13:01:57 2014] [warn] [client 85.87.112.225] mod_fcgid: stderr: PHP Fatal error: Call to a member function load() on a non-object in /var/www/vhosts/manualesdemecanica.com/httpdocs/administrator/components/com_content/models/articles.php on line 196, referer: www.manualesdemecanica.com/administrator...plugins&view=plugins
[Thu Apr 17 13:01:57 2014] [warn] [client 85.87.112.225] mod_fcgid: stderr: PHP Fatal error: Access to undeclared static property: JLoader::$classes in /var/www/vhosts/manualesdemecanica.com/httpdocs/libraries/loader.php on line 195, referer: www.manualesdemecanica.com/administrator...plugins&view=plugins
First off, I just updated your subscriptions on this site. You had individual subscriptions to JFBConnect and JLinked. JLinked was recently migrated into JFBConnect and is no longer available. Your subscriptions should have been merged together automatically, but for some reason weren't. I went ahead and just took care of that for you. Your JFBConnect subscription doesn't expire until early next year now.
As for your issue, the code change you made is still fine. I'm not sure why that change didn't make it into a release since last July. I've added it to our task list to investigate and make sure it gets into the next release, if it doesn't cause any other issues. The issue itself is strange and occurs because of how JomSocial overrides some core Joomla classes. Those changes are only meant to occur on the front-end, but are being inadvertently loaded by us in our plugin.
I hope that explains and glad you got things going. If you have any questions or run into any issues with the above change, please let us know.
System - JFBCSystem causing problems with Joomla articles in backend
