Example of a custom authentication solution for the Grails Spring Security Core Plugin. This was created to be a working guide to a blog post I wrote for the Object Partners blog http://www.objectpartners.com/2013/07/11/custom-authentication-with-the-grails-spring-security-core-plugin/
This program works as is, so feel free to download, try it out, or do whatever with it.
If you have any comments or questions hit me up at @JacobASeverson.