Some hosts set an open_basedir restriction. This means that only files from inside the set include_path are allowed.
your include_path is set to '/usr/lib/php'
but you are trying to require a file from '/www/zxq...'
and that is not in the allowed include_path.
Solutions are to set open_basedir off or to add your '/www' folder to the open_basedir include_path.
this should be done in your php.ini file (often located at /etc/php.ini) There you simply add the /www directory to you php.ini file. e.g. include_path='.:/usr/lib/php:/www/zxq.net'
If you don't have access to your php.ini file you can try setting it in php: http://php.net/manual/en/function.set-include-path.php if that doesn't work they don't allow you to edit the include_path. Contact your host and let them fix the problem.
EDIT: as linked to in the comments. See this thread for more info: open_basedir restriction in effect. File(/) is not within the allowed path(s):