By: Derek Berube, Wildstar Technologies, LLC.
Last Modified: July 10, 2014


After configuring a web application to use the second beta of the JSF 2.0 reference implementation and deploying it to the Google AppEngine platform the application failed to start.  The log files access through the application's AppEngine console reported the following error:
com.sun.faces.config.ConfigurationException: CONFIGURATION FAILED! is a restricted class. Please see the Google App
Engine developer's guide for more details.

comprehensive stack trace presented in the application's log is available.

Recommended Solution

One solution to this particular problem was to place copies of the serializer.jar and xalan.jar files from the 2.7.1 release of the Apache Xalan-J libraries into the web application's WEB-INF/lib directory.

Another solution is to ensure that the web application's WEB-INF/web.xml file explicitly sets the following parameters:
  • javax.faces.PROJECT_STAGE
  • com.sun.faces.enableMultiThreadedStartup
  • com.sun.el.ExpressionFactoryImpl

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