Fatal error when trying to activate the plugin

I got a fatal error message when i try to activate the Classified Maker plugin
Fatal error: Can't use function return value in write context in /var/www/web/wse75077701/pad.will.se/wp-content/plugins/classified-maker/includes/class-functions.php on line 419

Any solution for this?
Line 419 in class_functions.php is empty and as the noob i am i dont know what to do.