Java - Problema grave con jasper, necesaria vuestra ayuda

Muy buenas a tod@s. Os agradecería un segundo de vuestra atención. Tengo un problema con los jasper que no logro entender ni solucionar. Estoy desarrollando una aplicación web que quiero que me genere xls, para ello utilizo jasper's. Lo programé en local tal y como se indica en los ejemplos de los foros de los desarrolladores de la aplicación jasper y haciendo uso de las líbrerías que se indica en la misma página para jasperreports-1.2.2 que es la versión que utilizo. Incluso me he bajado el código y las librerías que allí utilizan en sus ejemplos para utilizarlas yo en mi aplicación. En local va como la seda, los típicos problemas iniciales de configuración pero va (consulte este mismo foro para solucionarlos). El problema surge cuando subo la aplicación a un servidor de aplicaciones j2ee. Lo subo en un ear que me genera mi programa e, increíblemente, cada vez que intento ejecutar el jasper me salta el siguiente error:
[Error de servlet]-[net/sf/jasperreports/engine/fill/JRVerticalFiller]: java.lang.NoClassDefFoundError: net/sf/jasperreports/engine/fill/JRVerticalFiller
java/lang/Throwable.<init>(Ljava/lang/String;)V+4 (Throwable.java:85)
java/lang/Error.<init>(Ljava/lang/String;)V+1 (Error.java:41)
java/lang/NoClassDefFoundError.<init>(Ljava/lang/String;)V+1 (NoClassDefFoundError.java:38)
net/sf/jasperreports/engine/fill/JRFiller.createFiller(Lnet/sf/jasperreports/engine/JasperReport;)Lnet/sf/jasperreports/engine/fill/JRBaseFiller;+44 (JRFiller.java:147)
net/sf/jasperreports/engine/fill/JRFiller.fillReport(Lnet/sf/jasperreports/engine/JasperReport;Ljava/util/Map;Ljava/sql/Connection;)Lnet/sf/jasperreports/engine/JasperPrint;+1 (JRFiller.java:57)
net/sf/jasperreports/engine/JasperFillManager.fillReport(Lnet/sf/jasperreports/engine/JasperReport;Ljava/util/Map;Ljava/sql/Connection;)Lnet/sf/jasperreports/engine/JasperPrint;+3 (JasperFillManager.java:402)
org/apache/jsp/_listado_5F_jasper._jspService(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+503 (_listado_5F_jasper.java:173)
com/ibm/ws/webcontainer/jsp/runtime/HttpJspBase.service(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+0 (HttpJspBase.java:89)
javax/servlet/http/HttpServlet.service(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (HttpServlet.java:848)
com/ibm/ws/webcontainer/jsp/servlet/JspServlet$JspServletWrapper.service(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;Z)V+225 (JspServlet.java:396)
com/ibm/ws/webcontainer/jsp/servlet/JspServlet.serviceJspFile(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;Ljava/lang/String;Ljava/lang/Throwable;ZLjava/lang/String;)V+97 (JspServlet.java:880)
com/ibm/ws/webcontainer/jsp/servlet/JspServlet.service(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+352 (JspServlet.java:978)
javax/servlet/http/HttpServlet.service(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (HttpServlet.java:848)
com/ibm/ws/webcontainer/servlet/StrictServletInstance.doService(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (StrictServletInstance.java:105)
com/ibm/ws/webcontainer/servlet/StrictLifecycleServlet._service(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (StrictLifecycleServlet.java:160)
com/ibm/ws/webcontainer/servlet/IdleServletState.service(Lcom/ibm/ws/webcontainer/servlet/StrictLifecycleServlet;Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (StrictLifecycleServlet.java:313)
com/ibm/ws/webcontainer/servlet/StrictLifecycleServlet.service(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (StrictLifecycleServlet.java:116)
com/ibm/ws/webcontainer/servlet/ServletInstance.service(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;Lcom/ibm/ws/webcontainer/webapp/WebAppServletInvocationEvent;)V+0 (ServletInstance.java:250)
com/ibm/ws/webcontainer/servlet/ValidServletReferenceState.dispatch(Lcom/ibm/ws/webcontainer/servlet/ServletInstanceReference;Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;Lcom/ibm/ws/webcontainer/webapp/WebAppServletInvocationEvent;)V+0 (ValidServletReferenceState.java:42)
com/ibm/ws/webcontainer/servlet/ServletInstanceReference.dispatch(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;Lcom/ibm/ws/webcontainer/webapp/WebAppServletInvocationEvent;)V+0 (ServletInstanceReference.java:40)
com/ibm/ws/webcontainer/webapp/WebAppRequestDispatcher.handleWebAppDispatch(Ljava x/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+0 (WebAppRequestDispatcher.java:936)
com/ibm/ws/webcontainer/webapp/WebAppRequestDispatcher.dispatch(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;Z)V+0 (WebAppRequestDispatcher.java:268)
com/ibm/ws/webcontainer/webapp/WebAppRequestDispatcher.forward(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (WebAppRequestDispatcher.java:155)
org/apache/struts/action/RequestProcessor.doForward(Ljava/lang/String;Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+0 (RequestProcessor.java:1058)
org/apache/struts/action/RequestProcessor.processForwardConfig(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;Lorg/apache/struts/config/ForwardConfig;)V+0 (RequestProcessor.java:428)
org/apache/struts/action/RequestProcessor.process(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+0 (RequestProcessor.java:217)
org/apache/struts/action/ActionServlet.process(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+0 (ActionServlet.java:1481)
org/apache/struts/action/ActionServlet.doPost(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+0 (ActionServlet.java:525)
javax/servlet/http/HttpServlet.service(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+0 (HttpServlet.java:733)
javax/servlet/http/HttpServlet.service(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (HttpServlet.java:848)
com/ibm/ws/webcontainer/servlet/StrictServletInstance.doService(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (StrictServletInstance.java:105)
com/ibm/ws/webcontainer/servlet/StrictLifecycleServlet._service(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (StrictLifecycleServlet.java:160)
com/ibm/ws/webcontainer/servlet/IdleServletState.service(Lcom/ibm/ws/webcontainer/servlet/StrictLifecycleServlet;Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (StrictLifecycleServlet.java:313)
com/ibm/ws/webcontainer/servlet/StrictLifecycleServlet.service(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (StrictLifecycleServlet.java:116)
com/ibm/ws/webcontainer/servlet/ServletInstance.service(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;Lcom/ibm/ws/webcontainer/webapp/WebAppServletInvocationEvent;)V+0 (ServletInstance.java:250)
com/ibm/ws/webcontainer/servlet/ValidServletReferenceState.dispatch(Lcom/ibm/ws/webcontainer/servlet/ServletInstanceReference;Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;Lcom/ibm/ws/webcontainer/webapp/WebAppServletInvocationEvent;)V+0 (ValidServletReferenceState.java:42)
com/ibm/ws/webcontainer/servlet/ServletInstanceReference.dispatch(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;Lcom/ibm/ws/webcontainer/webapp/WebAppServletInvocationEvent;)V+0 (ServletInstanceReference.java:40)
com/ibm/ws/webcontainer/webapp/WebAppRequestDispatcher.handleWebAppDispatch(Ljava x/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+0 (WebAppRequestDispatcher.java:936)
com/ibm/ws/webcontainer/webapp/WebAppRequestDispatcher.dispatch(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;Z)V+0 (WebAppRequestDispatcher.java:268)
com/ibm/ws/webcontainer/webapp/WebAppRequestDispatcher.forward(Ljavax/servlet/ServletRequest;Ljavax/servlet/ServletResponse;)V+0 (WebAppRequestDispatcher.java:155)
com/ibm/ws/webcontainer/srt/WebAppInvoker.doForward(Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse;)V+0 (WebAppInvoker.java:79)
com/ibm/ws/webcontainer/srt/WebAppInvoker.handleInvocationHook(Ljava/lang/Object;)V+0 (WebAppInvoker.java:159)
com/ibm/ws/webcontainer/cache/invocation/CachedInvocation.handleInvocation(Ljava/lang/Object;)V+0 (CachedInvocation.java:66)
com/ibm/ws/webcontainer/srp/ServletRequestProcessor.dispatchByURI(Ljava/lang/String;Lcom/ibm/ws/webcontainer/srp/ISRPConnection;)V+0 (ServletRequestProcessor.java:126)
com/ibm/ws/webcontainer/oselistener/OSEListenerDispatcher.service(Lcom/ibm/ws/webcontainer/oselistener/api/IOSEConnection;)V+0 (OSEListener.java:317)
com/ibm/ws/webcontainer/http/HttpConnection.handleRequest()V+0 (HttpConnection.java:56)
com/ibm/ws/http/HttpConnection.readAndHandleRequest(Z)V+0 (HttpConnection.java:575)
com/ibm/ws/http/HttpConnection.run()V+0 (HttpConnection.java:375)
com/ibm/ws/util/ThreadPool$Worker.run()V+0 (ThreadPool.java:654)

. No entiendo porque en local me funciona y en el servidor no. Creo que no faltan librerías pero ya me ha hecho dudar este error. ¿Alguien podría darme una pista? En tiempo de compilación no me indica que falte nada en el jsp, que es donde tengo todo el código para ejecutar el jasper. Ocurre en tiempo de ejecución. Sin nada más que daros las gracias por vuestra atención y esperando ansioso vuestras respuestas. Gracias.