...
The plugin could be downloaded from sourceforge at http://sfsourceforge.net/projects/japs/files/Community Plugins/jAPS2.0-Plugin-jpcasclient/.
More info about this and other jAPS 2.0 plugins could be found on the jAPS Community web site http://www.japsportal.org/ or on the mailinglists at the URL http://sourceforge.net/projects/japs/support.