The strange thing is that the exception is caught fine in the code so perhaps the issue is unrelated to the warning. In any case, for a tree, I sometimes see the case where the icons are only partially loaded and a browser refresh loads them properly but it's hard to make a test case since it doesn't happen every time.

Linking as a duplicate as the newer issue is a bit more generic and gets to the heart of the matter for all uses of the Util date formatter.

I still get

09:57:22,343 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[localhost].[/OSTi].[ICEfaces Resource Servlet]] Servlet.service() for servlet ICEfaces Resource Servlet threw exception: java.lang.NumberFormatException: For input string: "201201E.4201201E4"
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:1224) [:1.6.0_20]
at java.lang.Double.parseDouble(Double.java:510) [:1.6.0_20]
at java.text.DigitList.getDouble(DigitList.java:151) [:1.6.0_20]
at java.text.DecimalFormat.parse(DecimalFormat.java:1303) [:1.6.0_20]
at java.text.SimpleDateFormat.subParse(SimpleDateFormat.java:1591) [:1.6.0_20]
at java.text.SimpleDateFormat.parse(SimpleDateFormat.java:1312) [:1.6.0_20]
at java.text.DateFormat.parse(DateFormat.java:335) [:1.6.0_20]
at com.icesoft.faces.webapp.CompatResourceServlet.service(CompatResourceServlet.java:61) [:]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) [:1.0.0.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:324) [:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:242) [:]
at org.jboss.weld.servlet.ConversationPropagationFilter.doFilter(ConversationPropagationFilter.java:67) [:2010-11-18 09:06]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:274) [:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:242) [:]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [:]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) [:]
at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:181) [:6.0.0-SNAPSHOT]
at org.jboss.modcluster.catalina.CatalinaContext$RequestListenerValve.event(CatalinaContext.java:285) [:1.1.0.Final]
at org.jboss.modcluster.catalina.CatalinaContext$RequestListenerValve.invoke(CatalinaContext.java:261) [:1.1.0.Final]
at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:88) [:6.0.0-SNAPSHOT]
at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:100) [:6.0.0-SNAPSHOT]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) [:]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [:]
at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158) [:6.0.0-SNAPSHOT]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [:]
at org.jboss.web.tomcat.service.request.ActiveRequestResponseCacheValve.invoke(ActiveRequestResponseCacheValve.java:53) [:6.0.0-SNAPSHOT]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:362) [:]
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [:]
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:653) [:]
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:951) [:]
at java.lang.Thread.run(Thread.java:619) [:1.6.0_20]

on revision 23170

The issue remains. From trunk:

10:02:24,118 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[localhost].[/LTK].[ICEfaces Resource Servlet]] Servlet.service() for servlet ICEfaces Resource Servlet threw exception: java.lang.ArrayIndexOutOfBoundsException: -1
at java.text.DigitList.fitsIntoLong(DigitList.java:212) [:1.6.0_20]
at java.text.DecimalFormat.parse(DecimalFormat.java:1296) [:1.6.0_20]
at java.text.SimpleDateFormat.subParse(SimpleDateFormat.java:1936) [:1.6.0_20]
at java.text.SimpleDateFormat.parse(SimpleDateFormat.java:1312) [:1.6.0_20]
at java.text.DateFormat.parse(DateFormat.java:335) [:1.6.0_20]
at com.icesoft.faces.webapp.CompatResourceServlet.service(CompatResourceServlet.java:61) [:]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) [:1.0.0.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:324) [:6.0.0.20101110-CR1]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:242) [:6.0.0.20101110-CR1]
at org.jboss.weld.servlet.ConversationPropagationFilter.doFilter(ConversationPropagationFilter.java:67) [:2010-12-03 10:12]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:274) [:6.0.0.20101110-CR1]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:242) [:6.0.0.20101110-CR1]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [:6.0.0.20101110-CR1]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) [:6.0.0.20101110-CR1]
at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:181) [:6.0.0.20101110-CR1]
at org.jboss.modcluster.catalina.CatalinaContext$RequestListenerValve.event(CatalinaContext.java:285) [:1.1.0.Final]
at org.jboss.modcluster.catalina.CatalinaContext$RequestListenerValve.invoke(CatalinaContext.java:261) [:1.1.0.Final]
at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:88) [:6.0.0.20101110-CR1]
at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:100) [:6.0.0.20101110-CR1]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) [:6.0.0.20101110-CR1]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [:6.0.0.20101110-CR1]
at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158) [:6.0.0.20101110-CR1]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [:6.0.0.20101110-CR1]
at org.jboss.web.tomcat.service.request.ActiveRequestResponseCacheValve.invoke(ActiveRequestResponseCacheValve.java:53) [:6.0.0.20101110-CR1]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:362) [:6.0.0.20101110-CR1]
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [:6.0.0.20101110-CR1]
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:653) [:6.0.0.20101110-CR1]
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:951) [:6.0.0.20101110-CR1]
at java.lang.Thread.run(Thread.java:619) [:1.6.0_20]

and resources are not always delivered (in my example, some icons from the facets in a paginator went AWOL)