http://wiki.splitbrain.org/wiki:dokuwiki

For Ubuntu 8.04:

sudo apt-get install php5-cgi php5-gd dokuwiki

/etc/lighttpd/conf-available/10-dokuwiki.conf

# dokuwiki lighttpd config

url.rewrite-once = (                                                                                                   
        "^(/|index.php)?$" => "/doku.php",                                                                     
        "^/lib/(.*)/?$" => "/lib/$1",
        "^/_media/(.*)?\?(.*)$" => "/lib/exe/fetch.php?media=$1&$2",
        "^/_media/(.*)$" => "/lib/exe/fetch.php?media=$1",
        "^/_detail/(.*)?\?(.*)$" => "/lib/exe/detail.php?media=$1&$2",
        "^/_detail/(.*)?$" => "/lib/exe/detail.php?media=$1",
        "^/_export/([^/]+)/(.*)$" => "/doku.php?do=export_$1&id=$2",
        "^/(?!doku.php|feed.php|robots.txt|sitemap.xml.gz)(.*)\?(.*)/?$" => "/doku.php?id=$1&$2",
        "^/(?!doku.php|feed.php|robots.txt|sitemap.xml.gz|lib|_media|_detail|_export)(.*)/?$" => "/doku.php?id=$1",
)

sudo lighty-enable-mod dokuwiki
sudo /etc/init.d/lighttpd restart