E_WARNING: include(/www/federweg.ch/doc/wp-core/wp-trackback.php): failed to open stream: No such file or directory
  Trace: template-loader.php:40 template-loader.php:40 wp-blog-header.php:16 index.php:17
E_WARNING: include(): Failed opening '/www/federweg.ch/doc/wp-core/wp-trackback.php' for inclusion (include_path='/www/federweg.ch/phpinclude:/www/lib.search.ch/phpinclude:/www/server/phpinclude/itools:/www/server/phpinclude:/www/server/lib64/php:/www/server/lib/php')
  Trace: template-loader.php:40 template-loader.php:40 wp-blog-header.php:16 index.php:17