ERROR [org.apache.catalina.connector.CoyoteAdapter] An exception or error occurred in

CICA is getting this error on occasion and is wondering what it means does anyone have any ideas:

2011-04-26 13:15:12,895 ERROR [org.apache.catalina.connector.CoyoteAdapter] An exception or error occurred in the container during the request processing
java.lang.IndexOutOfBoundsException: Index: 1, Size: 1
at java.util.ArrayList.RangeCheck(Unknown Source)
at java.util.ArrayList.remove(Unknown Source)
at org.jboss.security.SecurityAssociation$RunAsThreadLocalStack.pop(SecurityAssociation.java:623)
at org.jboss.security.SecurityAssociation.popRunAsIdentity(SecurityAssociation.java:544)
at org.jboss.web.tomcat.security.SecurityAssociationActions$PopRunAsRoleAction.run(SecurityAssociationActions.java:113)
at java.security.AccessController.doPrivileged(Native Method)
at org.jboss.web.tomcat.security.SecurityAssociationActions.popRunAsIdentity(SecurityAssociationActions.java:171)
at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:160)
at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:59)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:856)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:744)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
at org.apache.tomcat.util.net.MasterSlaveWorkerThread.run(MasterSlaveWorkerThread.java:112)
at java.lang.Thread.run(Unknown Source)