"Another transaction by user ..." prompt while uploading appengine source

Problem Occurred:

Unable to update app: Error posting to URL: https://appengine.google.com/api/appversion/create?app_id=allenpettle324&version=1
409 Conflict
Another transaction by user allenshao.android is already in progress for this app and major version. That user can undo the transaction with appcfg.py's "rollback" command.

 

Using appcfg command to resolve this problem.

D:\Development\GAE\appengine-java-sdk-1.4.3\appengine-java-sdk-1.4.3\bin>appcfg.
cmd --email=[e-mail] --passin rollback D:\Development\WifiHot
spotSearch\war
Reading application configuration data...
2011-5-3 21:41:52 com.google.apphosting.utils.config.AppEngineWebXmlReader readAppEngineWebXml
信息: Successfully processed D:/Development/WifiHotspotSearch/war\WEB-INF/appengine-web.xml
2011-5-3 21:41:52 com.google.apphosting.utils.config.AbstractConfigXmlReader rea
dConfigXml
信息: Successfully processed D:/Development/WifiHotspotSearch/war\WEB-INF/web.xml
2011-5-3 21:41:52 com.google.apphosting.utils.config.IndexesXmlReader readConfigXml
信息: Successfully processed D:\Development\WifiHotspotSearch\war\WEB-INF\appeng
ine-generated\datastore-indexes-auto.xml
Beginning server interaction for allenpettle324...
0% Rolling back the update.
Success.
Cleaning up temporary files...