解决Hudson部署的错误

部署hudson到JBoss5.1下，出现severe日志如下：

22:04:16,219 SEVERE [ComputerSet] Failed to instanciate class hudson.node_monito
rs.DiskSpaceMonitor
java.lang.InstantiationException: hudson.node_monitors.DiskSpaceMonitor
        at java.lang.Class.newInstance0(Class.java:340)
        at java.lang.Class.newInstance(Class.java:308)
        at hudson.model.ComputerSet.createDefaultInstance(ComputerSet.java:381)
        at hudson.model.ComputerSet.<clinit>(ComputerSet.java:369)
        at hudson.model.LoadStatistics$LoadStatisticsUpdater.doRun(LoadStatistic
s.java:214)
        at hudson.triggers.SafeTimerTask.run(SafeTimerTask.java:54)
        at java.util.TimerThread.mainLoop(Timer.java:512)
        at java.util.TimerThread.run(Timer.java:462)
22:04:16,219 SEVERE [ComputerSet] Failed to instanciate class hudson.node_monito
rs.TemporarySpaceMonitor
java.lang.InstantiationException: hudson.node_monitors.TemporarySpaceMonitor
        at java.lang.Class.newInstance0(Class.java:340)
        at java.lang.Class.newInstance(Class.java:308)
        at hudson.model.ComputerSet.createDefaultInstance(ComputerSet.java:381)
        at hudson.model.ComputerSet.<clinit>(ComputerSet.java:369)
        at hudson.model.LoadStatistics$LoadStatisticsUpdater.doRun(LoadStatistic
s.java:214)
        at hudson.triggers.SafeTimerTask.run(SafeTimerTask.java:54)
        at java.util.TimerThread.mainLoop(Timer.java:512)
        at java.util.TimerThread.run(Timer.java:462)

解决方法：
修改USER_HOME的.hudson\nodeMonitors.xml
（windows下是C:\Users\XXX\.hudson）
添加如下内容：

<hudson.node__monitors.TemporarySpaceMonitor>
<ignored>false</ignored>
</hudson.node__monitors.TemporarySpaceMonitor>
<hudson.node__monitors.DiskSpaceMonitor>
<ignored>false</ignored>
</hudson.node__monitors.DiskSpaceMonitor>

然后重启JBoss。

原因及原理不明 - -！

参考文章：
http://paste.lisp.org/display/92731