Install XDoclet into maven

1. download the maven-xdoclet-plugin
     方法 可以在 project.xml 中 添加 dependency, 通过 maven war 的方式得到 maven-xdoclet-plugin-1.2.jar
2. 将plug-in jar 文件copy 到 $MAVEN_HOME/plugins
3. 清空 $USER_HOME/.maven/cache
4. 再跑 maven war
     此时将会出现如下错误：
    Tag library requested that is not present: 'maven' in plugin: 'maven-xdoclet-plugin-1.2'
???????? commons-logging-1.1-dev.jar????
21K downloaded
???????? log4j-1.2.6.jar????
342K downloaded
???????? xjavadoc-1.0.2.jar????
233K downloaded
BUILD FAILED
File...... C:/Documents and Settings/victorw/.maven/cache/maven-xdoclet-plugin-1.2/plugin.jelly
Element... taskdef
Line...... 10255
Column.... 99
taskdef class xdoclet.modules.hibernate.HibernateDocletTask cannot be found
5. 在 project.xml 中添加相应的 dependencies
    例如 xjavadoc, log4j, commons-logging