这是我收到的错误。当我恢复使用6u30时，它可以正常工作。AppEngine必须立即更新以解决此错误。

Initializing App Engine server
   [ERROR] Unable to start App Engine server
Unable to start embedded HTTP serverjava.lang.RuntimeException: Unable to restore the previous TimeZone
at com.google.appengine.tools.development.DevAppServerImpl.restoreLocalTimeZone(DevAppServerImpl.java:228)
at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:164)
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)
Caused by: java.lang.NoSuchFieldException: defaultZoneTL
at java.lang.Class.getDeclaredField(Unknown Source)
at com.google.appengine.tools.development.DevAppServerImpl.restoreLocalTimeZone(DevAppServerImpl.java:222)
... 6 more
[ERROR] shell failed in doStartupServer method

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)