Websphere 6.0 page navigation problem

[Khurram Ahmed]

MyFaces version:  1.1.1
Tomact version: 5.0.27

I have an application that was developed on tomcat 5.0.27 that refuses to work properly on websphere 6.0 i am able to access the opening page after logging however any subsequent attempts at navigation through a link menu in the application generates the following errors..............

Error Message:
Error Code: 500
Target Servlet: action
Error Stack:
java.lang.NullPointerException
     at com.ibm.websphere.product.WASProduct.listFileNames(WASProduct.java:2251)
     at com.ibm.websphere.product.WASProduct.listFileNames(WASProduct.java:2244)
     at com.ibm.websphere.product.WASProduct.basicGetProductNames(WASProduct.java:1467)
     at com.ibm.websphere.product.WASProduct.getProductNames(WASProduct.java:1460)
     at com.ibm.websphere.product.WASProduct.basicGetProducts(WASProduct.java:1429)
     at com.ibm.websphere.product.WASProduct.getProducts(WASProduct.java:1422)
     at com.ibm.websphere.product.WASProduct.getProductById(WASProduct.java:942)
     at com.ibm.websphere.product.WASProduct.productPresent(WASProduct.java:968)
     at _ibmjsp.secure.layouts._contentLayout._jspService(_contentLayout.java:467)
     at com.ibm.ws.jsp.runtime.HttpJspBase.service(HttpJspBase.java:88)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
     at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1212)
     at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:629)
     at com.ibm.wsspi.webcontainer.servlet.GenericServletWrapper.handleRequest(GenericServletWrapper.java:117)
     at com.ibm.ws.jsp.webcontainerext.JSPExtensionServletWrapper.handleRequest(JSPExtensionServletWrapper.java:171)
     at com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.forward(WebAppRequestDispatcher.java:250)
     at org.apache.struts.action.RequestProcessor.doForward(RequestProcessor.java:1070)
     at org.apache.struts.tiles.TilesRequestProcessor.doForward(TilesRequestProcessor.java:273)
     at org.apache.struts.tiles.TilesRequestProcessor.processTilesDefinition(TilesRequestProcessor.java:253)
     at org.apache.struts.tiles.TilesRequestProcessor.processForwardConfig(TilesRequestProcessor.java:308)
     at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:279)
     at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1486)
     at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:510)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:743)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
     at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1212)
     at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:629)
     at com.ibm.ws.webcontainer.webapp.WebApp.handleRequest(WebApp.java:2841)
     at com.ibm.ws.webcontainer.webapp.WebGroup.handleRequest(WebGroup.java:220)
     at com.ibm.ws.webcontainer.VirtualHost.handleRequest(VirtualHost.java:204)
     at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:1681)
     at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:77)
     at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:421)
     at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewInformation(HttpInboundLink.java:367)
     at com.ibm.ws.http.channel.inbound.impl.HttpICLReadCallback.complete(HttpICLReadCallback.java:94)
     at com.ibm.ws.tcp.channel.impl.WorkQueueManager.requestComplete(WorkQueueManager.java:548)
     at com.ibm.ws.tcp.channel.impl.WorkQueueManager.attemptIO(WorkQueueManager.java(Compiled Code))
     at com.ibm.ws.tcp.channel.impl.WorkQueueManager.workerRun(WorkQueueManager.java:934)
     at com.ibm.ws.tcp.channel.impl.WorkQueueManager$Worker.run(WorkQueueManager.java:1021)
     at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java(Compiled Code))
    

any solutions or workarounds or hints about the reason for this error