An error occurred
The org.apache.cocoon.www.sitemap_xmap notifies that org.apache.cocoon.ProcessingException says:

Exception JspGenerator.generate()

More precisely:

org.apache.cocoon.ProcessingException: Exception JspGenerator.generate(): java.lang.ClassCastException: org.apache.cocoon.components.jsp.JSPEngineImplNamedDispatcherInclude$MyServletRequest

extra info
full exception chain stacktrace
Original exception : java.lang.ClassCastException: org.apache.cocoon.components.jsp.JSPEngineImplNamedDispatcherInclude$MyServletRequest
at weblogic.servlet.internal.RequestDispatcherImpl.include(RequestDispatcherImpl.java:211)
at weblogic.servlet.internal.RequestDispatcherImpl.include(RequestDispatcherImpl.java:183)
at org.apache.cocoon.components.jsp.JSPEngineImplNamedDispatcherInclude.executeJSP(JSPEngineImplNamedDispatcherInclude.java:126)
at org.apache.cocoon.generation.JspGenerator.generate(JspGenerator.java:116)
at org.apache.cocoon.components.pipeline.CachingEventPipeline.process(CachingEventPipeline.java:251)
at org.apache.cocoon.components.pipeline.CachingStreamPipeline.process(CachingStreamPipeline.java:399)
at org.apache.cocoon.www.sitemap_xmap.matchN10779(C:\bea\wlserver6.0\config\mydomain\applications\cocoon\WEB-INF\_tmp_war_myserver_myserver_cocoon\cocoon-files\org/apache/cocoon/www\sitemap_xmap.java:9352)
at org.apache.cocoon.www.sitemap_xmap.process(C:\bea\wlserver6.0\config\mydomain\applications\cocoon\WEB-INF\_tmp_war_myserver_myserver_cocoon\cocoon-files\org/apache/cocoon/www\sitemap_xmap.java:3620)
at org.apache.cocoon.www.sitemap_xmap.process(C:\bea\wlserver6.0\config\mydomain\applications\cocoon\WEB-INF\_tmp_war_myserver_myserver_cocoon\cocoon-files\org/apache/cocoon/www\sitemap_xmap.java:3085)
at org.apache.cocoon.sitemap.Handler.process(Handler.java:222)
at org.apache.cocoon.sitemap.Manager.invoke(Manager.java:179)
at org.apache.cocoon.sitemap.SitemapManager.process(SitemapManager.java:154)
at org.apache.cocoon.Cocoon.process(Cocoon.java:575)
at org.apache.cocoon.servlet.CocoonServlet.service(CocoonServlet.java:998)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:213)
at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:1265)
at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:1631)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:137)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)

stacktrace
org.apache.cocoon.ProcessingException: Exception JspGenerator.generate(): java.lang.ClassCastException: org.apache.cocoon.components.jsp.JSPEngineImplNamedDispatcherInclude$MyServletRequest
at org.apache.cocoon.generation.JspGenerator.generate(JspGenerator.java:140)
at org.apache.cocoon.components.pipeline.CachingEventPipeline.process(CachingEventPipeline.java:251)
at org.apache.cocoon.components.pipeline.CachingStreamPipeline.process(CachingStreamPipeline.java:399)
at org.apache.cocoon.www.sitemap_xmap.matchN10779(C:\bea\wlserver6.0\config\mydomain\applications\cocoon\WEB-INF\_tmp_war_myserver_myserver_cocoon\cocoon-files\org/apache/cocoon/www\sitemap_xmap.java:9352)
at org.apache.cocoon.www.sitemap_xmap.process(C:\bea\wlserver6.0\config\mydomain\applications\cocoon\WEB-INF\_tmp_war_myserver_myserver_cocoon\cocoon-files\org/apache/cocoon/www\sitemap_xmap.java:3620)
at org.apache.cocoon.www.sitemap_xmap.process(C:\bea\wlserver6.0\config\mydomain\applications\cocoon\WEB-INF\_tmp_war_myserver_myserver_cocoon\cocoon-files\org/apache/cocoon/www\sitemap_xmap.java:3085)
at org.apache.cocoon.sitemap.Handler.process(Handler.java:222)
at org.apache.cocoon.sitemap.Manager.invoke(Manager.java:179)
at org.apache.cocoon.sitemap.SitemapManager.process(SitemapManager.java:154)
at org.apache.cocoon.Cocoon.process(Cocoon.java:575)
at org.apache.cocoon.servlet.CocoonServlet.service(CocoonServlet.java:998)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:213)
at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:1265)
at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:1631)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:137)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)
java.lang.ClassCastException: org.apache.cocoon.components.jsp.JSPEngineImplNamedDispatcherInclude$MyServletRequest
at weblogic.servlet.internal.RequestDispatcherImpl.include(RequestDispatcherImpl.java:211)
at weblogic.servlet.internal.RequestDispatcherImpl.include(RequestDispatcherImpl.java:183)
at org.apache.cocoon.components.jsp.JSPEngineImplNamedDispatcherInclude.executeJSP(JSPEngineImplNamedDispatcherInclude.java:126)
at org.apache.cocoon.generation.JspGenerator.generate(JspGenerator.java:116)
at org.apache.cocoon.components.pipeline.CachingEventPipeline.process(CachingEventPipeline.java:251)
at org.apache.cocoon.components.pipeline.CachingStreamPipeline.process(CachingStreamPipeline.java:399)
at org.apache.cocoon.www.sitemap_xmap.matchN10779(C:\bea\wlserver6.0\config\mydomain\applications\cocoon\WEB-INF\_tmp_war_myserver_myserver_cocoon\cocoon-files\org/apache/cocoon/www\sitemap_xmap.java:9352)
at org.apache.cocoon.www.sitemap_xmap.process(C:\bea\wlserver6.0\config\mydomain\applications\cocoon\WEB-INF\_tmp_war_myserver_myserver_cocoon\cocoon-files\org/apache/cocoon/www\sitemap_xmap.java:3620)
at org.apache.cocoon.www.sitemap_xmap.process(C:\bea\wlserver6.0\config\mydomain\applications\cocoon\WEB-INF\_tmp_war_myserver_myserver_cocoon\cocoon-files\org/apache/cocoon/www\sitemap_xmap.java:3085)
at org.apache.cocoon.sitemap.Handler.process(Handler.java:222)
at org.apache.cocoon.sitemap.Manager.invoke(Manager.java:179)
at org.apache.cocoon.sitemap.SitemapManager.process(SitemapManager.java:154)
at org.apache.cocoon.Cocoon.process(Cocoon.java:575)
at org.apache.cocoon.servlet.CocoonServlet.service(CocoonServlet.java:998)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:213)
at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:1265)
at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:1631)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:137)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)
original messagejava.lang.ClassCastException: org.apache.cocoon.components.jsp.JSPEngineImplNamedDispatcherInclude$MyServletRequest

If you need help and this information is not enough, you are invited to read the cocoon faq.
If you still don't find the answers you need, can send a mail to the Cocoon users mailing list, remembering to
  • specify the version of Cocoon you're using, or we suppose that you are talking about the latest version;
  • specify the taglibs and sitemap components that are pertinent;
  • specify the platform-operating system-version-servlet container version;
  • send any pertinent error message;
  • send pertinent log snippets;
  • send pertinent sitemap snippets;
  • send pertinent parts of the page that gives you problems.
For more detailed technical information, take a look at the log files in the log directory of cocoon, which is /WEB-INF/logs by default.
Logging configuration is by default in /WEB-INF/logkit.xconf.

If you think you found a bug, please report it to Apache's Bugzilla; a message will be sent to the developer mailing list.