Classifier4J is a Java library designed to do text classification. It comes with an implementation of a Bayesian classifier, and now has some other features, including a text summary facility.
I usually keep my blog updated with development progress and future directions.
Classifier4J 0.6 is available for download. See the news for further information. Note that the cvs module name has changed (to newbuild) if you retrieve it via CVS.
Classifier4J 0.51 is available for download. See the news for further information.