Andreas Gohr at Splitbrain has released a plugin that allows you to use DISQUS on DokuWiki. 

Find it here: http://www.dokuwiki.org/plugin:disqus

Getting Started!

• Click Admin
  This assumes you have properly setup your super user, If not read this.
• Click Manage Plugins
• Copy/Paste the plugin download link in the field URL.
   
• Click download
• Return to the homepage
• Click Admin
• Click Configuration Settings
• Click Disqus Plugin Settings under Table of Contents
• Enter your forum shortname
• Add ~~DISQUS~~ where you would like your comments

And voila that’s all there is to it! Thank you Andreas for your hard work!