This is fall-out from adding the attribute copying for the Seam debug page. With Seam, when doing a file upload, it will occasionally throw the following exception. We can consume the exception, but it's not clear how to avoid the situation from occurring in the first place.

NPE:
org.apache.catalina.connector.Request.setAttribute(Request.java:1424)
org.apache.catalina.connector.RequestFacade.setAttribute(RequestFacade.java:503)
javax.servlet.ServletRequestWrapper.setAttribute(ServletRequestWrapper.java:284)
com.icesoft.faces.webapp.http.servlet.ServletRequestAttributes.setAttribute(ServletRequestAttributes.java:28)
com.icesoft.faces.webapp.http.servlet.ServletEnvironmentRequest.setAttribute(ServletEnvironmentRequest.java:216)
com.icesoft.faces.webapp.http.servlet.ServletRequestAttributeMap.setAttribute(ServletRequestAttributeMap.java:25)
com.icesoft.faces.context.AbstractCopyingAttributeMap.put(AbstractCopyingAttributeMap.java:22)
java.util.Collections$SynchronizedMap.put(Collections.java:1983)
com.sun.faces.util.RequestStateManager.getStateMap(RequestStateManager.java:281)
com.sun.faces.util.RequestStateManager.set(RequestStateManager.java:223)
com.sun.faces.el.FacesCompositeELResolver.setChainType(FacesCompositeELResolver.java:159)
com.sun.faces.el.FacesCompositeELResolver.getValue(FacesCompositeELResolver.java:71)
org.jboss.el.parser.AstIdentifier.getValue(AstIdentifier.java:44)
org.jboss.el.parser.AstValue.getTarget(AstValue.java:34)
org.jboss.el.parser.AstValue.invoke(AstValue.java:95)
org.jboss.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276)
com.sun.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:68)
com.sun.facelets.el.LegacyMethodBinding.invoke(LegacyMethodBinding.java:69)
com.icesoft.faces.component.inputfile.InputFile.setProgress(InputFile.java:945)
com.icesoft.faces.component.inputfile.InputFile.setProgressSafely(InputFile.java:929)
com.icesoft.faces.component.inputfile.InputFile.updateProgress(InputFile.java:955)
com.icesoft.faces.webapp.http.core.UploadServer$ProgressCalculator.potentiallyNotify(UploadServer.java:195)
com.icesoft.faces.webapp.http.core.UploadServer$ProgressCalculator.potentiallyNotify(UploadServer.java:182)
com.icesoft.faces.webapp.http.core.UploadServer$ProgressCalculator.setListenerAndContextAndPFS(UploadServer.java:162)
com.icesoft.faces.webapp.http.core.UploadServer$2.servlet(UploadServer.java:78)
com.icesoft.faces.webapp.http.servlet.ServletRequestResponse.detectEnvironment(ServletRequestResponse.java:228)
com.icesoft.faces.webapp.http.core.UploadServer.service(UploadServer.java:52)
com.icesoft.faces.webapp.http.common.standard.PathDispatcherServer.service(PathDispatcherServer.java:24)
com.icesoft.faces.webapp.http.servlet.MainSessionBoundServlet.service(MainSessionBoundServlet.java:160)
com.icesoft.faces.webapp.http.servlet.SessionDispatcher$1.service(SessionDispatcher.java:38)
com.icesoft.faces.webapp.http.servlet.ThreadBlockingAdaptingServlet.service(ThreadBlockingAdaptingServlet.java:19)
com.icesoft.faces.webapp.http.servlet.EnvironmentAdaptingServlet.service(EnvironmentAdaptingServlet.java:63)
com.icesoft.faces.webapp.http.servlet.SessionDispatcher.service(SessionDispatcher.java:55)
com.icesoft.faces.webapp.http.servlet.PathDispatcher.service(PathDispatcher.java:23)
com.icesoft.faces.webapp.http.servlet.MainServlet.service(MainServlet.java:91)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
com.icesoft.faces.webapp.xmlhttp.BlockingServlet.service(BlockingServlet.java:56)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83)
org.jboss.seam.debug.hot.HotDeployFilter.doFilter(HotDeployFilter.java:44)
org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:58)
org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64)
org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
org.jboss.seam.web.IdentityFilter.doFilter(IdentityFilter.java:38)
org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:45)
org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230)
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:182)
org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:262)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:446)
java.lang.Thread.run(Thread.java:595)