Oops, I am using 1.51. Not sure about init_html_editor.php. It has this in the list of editors.

if (is_dir(DIR_FS_CATALOG . DIR_WS_EDITORS . 'ckeditor')) $editors_list['CKEDITOR'] = array('desc' => EDITOR_CKEDITOR, 'handler' => 'ckeditor.php', 'special_needs' => '');