Google app engine hello world program doesn't work

Google app engine hello world program doesn't work

I installed eclipse GAE plugin, followed this simple tutorial, and when I
run my program I get the error message
Initializing App Engine server
àåâ 23, 2013 12:54:04 PM
com.google.apphosting.utils.config.AppEngineWebXmlReader
readAppEngineWebXml
INFO: Successfully processed
C:\Users\Owner\workspace\GoogleTest2\war\WEB-INF/appengine-web.xml
àåâ 23, 2013 12:54:04 PM
com.google.apphosting.utils.config.AppEngineWebXmlReader
readAppEngineWebXml
SEVERE: Received exception processing
C:\Users\Owner\workspace\GoogleTest2\war\WEB-INF/appengine-web.xml
com.google.apphosting.utils.config.AppEngineConfigException:
appengine-web.xml does not contain a <threadsafe> element.
See
http://code.google.com/appengine/docs/java/config/appconfig.html#Using_Concurrent_Requests
for more information.
You probably want to enable concurrent requests.
at
com.google.apphosting.utils.config.AppEngineWebXmlReader.readAppEngineWebXml(AppEngineWebXmlReader.java:85)
at
com.google.apphosting.utils.config.EarHelper.readWebModule(EarHelper.java:166)
at
com.google.appengine.tools.development.ApplicationConfigurationManager$WarModuleConfigurationHandle.readConfiguration(ApplicationConfigurationManager.java:399)
at
com.google.appengine.tools.development.ApplicationConfigurationManager.<init>(ApplicationConfigurationManager.java:146)
at
com.google.appengine.tools.development.ApplicationConfigurationManager.newWarConfigurationManager(ApplicationConfigurationManager.java:88)
at
com.google.appengine.tools.development.DevAppServerImpl.<init>(DevAppServerImpl.java:137)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native
Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown
Source)
at
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown
Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at
com.google.appengine.tools.development.DevAppServerFactory.createDevAppServer(DevAppServerFactory.java:233)
at
com.google.appengine.tools.development.DevAppServerFactory.createDevAppServer(DevAppServerFactory.java:69)
at
com.google.appengine.tools.development.DevAppServerFactory.createDevAppServer(DevAppServerFactory.java:53)
at
com.google.appengine.tools.development.gwt.AppEngineLauncher.start(AppEngineLauncher.java:84)
at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1093)
at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:836)
at com.google.gwt.dev.DevMode.main(DevMode.java:311)
[ERROR] Unable to start App Engine server
com.google.apphosting.utils.config.AppEngineConfigException: Invalid
configuration
at
com.google.appengine.tools.development.DevAppServerImpl.reportDeferredConfigurationException(DevAppServerImpl.java:414)
at
com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:211)
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:1093)
at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:836)
at com.google.gwt.dev.DevMode.main(DevMode.java:311)
Caused by: com.google.apphosting.utils.config.AppEngineConfigException:
Invalid
appengine-web.xml(C:\Users\Owner\workspace\GoogleTest2\war\WEB-INF/appengine-web.xml)
- appengine-web.xml does not contain a <threadsafe> element.
See
http://code.google.com/appengine/docs/java/config/appconfig.html#Using_Concurrent_Requests
for more information.
You probably want to enable concurrent requests.
at
com.google.apphosting.utils.config.EarHelper.readWebModule(EarHelper.java:168)
at
com.google.appengine.tools.development.ApplicationConfigurationManager$WarModuleConfigurationHandle.readConfiguration(ApplicationConfigurationManager.java:399)
at
com.google.appengine.tools.development.ApplicationConfigurationManager.<init>(ApplicationConfigurationManager.java:146)
at
com.google.appengine.tools.development.ApplicationConfigurationManager.newWarConfigurationManager(ApplicationConfigurationManager.java:88)
at
com.google.appengine.tools.development.DevAppServerImpl.<init>(DevAppServerImpl.java:137)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native
Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown
Source)
at
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown
Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at
com.google.appengine.tools.development.DevAppServerFactory.createDevAppServer(DevAppServerFactory.java:233)
at
com.google.appengine.tools.development.DevAppServerFactory.createDevAppServer(DevAppServerFactory.java:69)
at
com.google.appengine.tools.development.DevAppServerFactory.createDevAppServer(DevAppServerFactory.java:53)
at
com.google.appengine.tools.development.gwt.AppEngineLauncher.start(AppEngineLauncher.java:84)
... 4 more
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:1093)
at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:836)
at com.google.gwt.dev.DevMode.main(DevMode.java:311)
[ERROR] shell failed in doStartupServer method
Any ideas why? Thanks!