AbstractMethodError with Struts / Tiles in JBoss EAP

Issue

• Struts / Tiles application is failing with the AbstractMethodError below :

10:10:10,230 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/ExampleRequest]] (ServerService Thread Pool -- 64) JBWEB000289: Servlet action threw load() exception: java.lang.AbstractMethodError: org.apache.struts.tiles.TilesPlugin.init(Lorg/apache/struts/action/ActionServlet;Lorg/apache/struts/config/ModuleConfig;)V
  at org.apache.struts.action.ActionServlet.initModulePlugIns(ActionServlet.java:1158) [struts.jar:1.1]
  at org.apache.struts.action.ActionServlet.init(ActionServlet.java:473) [struts.jar:1.1]
  at javax.servlet.GenericServlet.init(GenericServlet.java:242) [jboss-servlet-api_3.0_spec-1.0.2.Final-redhat-2.jar:1.0.2.Final-redhat-2]
  at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1206) [jbossweb-7.5.9.Final-redhat-1.jar:7.5.9.Final-redhat-1]
  at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1112) [jbossweb-7.5.9.Final-redhat-1.jar:7.5.9.Final-redhat-1]
  at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:3593) [jbossweb-7.5.9.Final-redhat-1.jar:7.5.9.Final-redhat-1]
  at org.apache.catalina.core.StandardContext.start(StandardContext.java:3802) [jbossweb-7.5.9.Final-redhat-1.jar:7.5.9.Final-redhat-1]
  at org.jboss.as.web.deployment.WebDeploymentService.doStart(WebDeploymentService.java:163) [jboss-as-web-7.5.2.Final-redhat-2.jar:7.5.2.Final-redhat-2]
  at org.jboss.as.web.deployment.WebDeploymentService.access$000(WebDeploymentService.java:61) [jboss-as-web-7.5.2.Final-redhat-2.jar:7.5.2.Final-redhat-2]
  at org.jboss.as.web.deployment.WebDeploymentService$1.run(WebDeploymentService.java:96) [jboss-as-web-7.5.2.Final-redhat-2.jar:7.5.2.Final-redhat-2]
  at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [rt.jar:1.8.0_51]
  at java.util.concurrent.FutureTask.run(FutureTask.java:266) [rt.jar:1.8.0_51]
  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [rt.jar:1.8.0_51]
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [rt.jar:1.8.0_51]
  at java.lang.Thread.run(Thread.java:745) [rt.jar:1.8.0_51]
  at org.jboss.threads.JBossThread.run(JBossThread.java:122)