This plugin is a wrapper to the xmlbean ant task (see http://xml.apache.org/xmlbeans/ for more information on XMLBeans) which generates and compiles XMLBeans from XML Schema (*.xsd) files.
By default the plugin looks for the XML Schema files in the src/xmlbeans directory. Java source files for the generated XMLBeans are put into the target/xmlbeans/src directory. Class files and generated resource files are compiled into the target/classes directory. The plugin also creates a jar file (containing the generated class and resource files) which is put into the target/xmlbeans directory.
You will need the XMLBean's xbean.jar file to use this plugin. You can get the jar from http://xml.apache.org/xmlbeans/. The project.xml currently will download the xbeans-1.0-DEV.jar from http://www.ibiblio.org/maven/xmlbeans/jars/. As new releases are made the dependency will have to changed in the project.xml