Ramoonus

It`s compatible with 2.8.5 on my blog

Yeeha,
no more W3C validation errors

this plugin is out-dated ??

the only thing you have to do is enable the plugin and make the caching folder
as in the readme

Having the same problem
running on php 5.2 / mysql 5.0
WordPress 2.7.1, enabled Akismet and WP Stats

I`ve updated to the latest K2 nighty build, problem has been fixed.