Fatal error: Uncaught Error: Class 'Ai1ec_Command' not found in /srv/drbd-web/home/chelix/public_html/wp-content/plugins/all-in-one-event-calendar/lib/command/compile-core-css.php on line 11

Error: Class 'Ai1ec_Command' not found in /srv/drbd-web/home/chelix/public_html/wp-content/plugins/all-in-one-event-calendar/lib/command/compile-core-css.php on line 11

Call Stack:
    0.0008     359784   1. {main}() /srv/drbd-web/home/chelix/public_html/wp-content/plugins/all-in-one-event-calendar/lib/command/compile-core-css.php:0