This plugin allows to define build environment as a Dockerfile, stored in project SCM. see also http://wiki.jenkins-ci.org/display/JENKINS/Oki+Docki+Plugin
cause there's already a "Docker" plugin, with a very distinct approach
We made this project production ready (more or less) during Docker Global Hack Day. Please vote for us on https://www.docker.com/community/globalhackday/14