为什么我的appengine服务器不再启动了？
操作系统：Windows 7 应用服务引擎的Java-SDK-1.6.3.1
错误输出：
23-mar-2012 21.26.29 com.google.apphosting.utils.jetty.JettyLogger info
INFO: Logging to JettyLogger(null) via com.google.apphosting.utils.jetty.JettyLogger
Initializing App Engine server
[ERROR] Unable to start App Engine server
java.lang.NullPointerException
at com.google.apphosting.utils.io.IoUtil.getFiles(IoUtil.java:34)
at com.google.apphosting.utils.io.IoUtil.getFiles(IoUtil.java:35)
at com.google.apphosting.utils.io.IoUtil.getFiles(IoUtil.java:35)
at com.google.apphosting.utils.io.IoUtil.getFiles(IoUtil.java:35)
at com.google.apphosting.utils.io.IoUtil.getFilesAndDirectories(IoUtil.java:28)
at com.google.appengine.tools.development.IsolatedAppClassLoader.buildPermissionsToReadAppFiles(IsolatedAppClassLoader.java:373)
at com.google.appengine.tools.development.IsolatedAppClassLoader.createAppPermissions(IsolatedAppClassLoader.java:204)
at com.google.appengine.tools.development.IsolatedAppClassLoader.<init>(IsolatedAppClassLoader.java:61)
at com.google.appengine.tools.development.JettyContainerService.initContext(JettyContainerService.java:153)
at com.google.appengine.tools.development.AbstractContainerService.startup(AbstractContainerService.java:236)
at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:146)
at com.google.appengine.tools.development.gwt.AppEngineLauncher.start(AppEngineLauncher.java:97)
at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068)
at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811)
at com.google.gwt.dev.DevMode.main(DevMode.java:311)
Unable to start embedded HTTP server
com.google.gwt.core.ext.UnableToCompleteException: (see previous log entries)
at com.google.appengine.tools.development.gwt.AppEngineLauncher.start(AppEngineLauncher.java:102)
at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068)
at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811)
at com.google.gwt.dev.DevMode.main(DevMode.java:311)
[ERROR] shell failed in doStartupServer method
我疯了......