According to the XDoclet doc
"You have to make sure tools.jar from JDK's lib directory is on your classpath, and that you are using Jakarta Ant 1.5 or higher (XDoclet does not support previous versions)."
So you should upgrade your Ant, since you are using an old one. I haven't tried xdoclet myself so I don't know if that will be enough, but you definitely need to upgrade your Ant.
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