Warning: file_exists() [function.file-exists]: open_basedir restriction in effect. File(/var/www/vhosts/neohoster.net/wp-config.php) is not within the allowed path(s): (/var/www/vhosts/neohoster.net/httpdocs/:/tmp/) in /var/www/vhosts/neohoster.net/httpdocs/wp-load.php on line 31
Your server is running PHP version 5.1.6 but WordPress 3.3.2 requires at least 5.2.4.