ERROR: Wrong agrument type passed to HTMLTag->add_to()
#0  core_error(Wrong agrument type passed to HTMLTag->add_to()) called at [/home/opgw/k12beta/html.php:111]
#1  HTMLContainer->add_to(Array (), , 1) called at [/home/opgw/k12beta/html.php:125]
#2  HTMLContainer->add() called at [/home/opgw/k12beta/subpages/main.php:24]
#3  main_main(Array ([0] => view,[1] => 622))
#4  call_user_func(main_main, Array ([0] => view,[1] => 622)) called at [/home/opgw/k12beta/index.php:83]