Problem displaying login screen

Problem displaying login screen

When I open my browser, (Mozilla Firefox Ver 1.0.6, or Internet Explorer Ver 6) it does not shows the images correctly, and if I login I get the following error message:

HTTP Status 500 -

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type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

java.lang.NullPointerException
org.apache.catalina.loader.WebappClassLoader.findResourceInternal(WebappClassLoader.java:1774)
org.apache.catalina.loader.WebappClassLoader.findResource(WebappClassLoader.java:920)
org.apache.catalina.loader.WebappClassLoader.getResourceAsStream(WebappClassLoader.java:1138)
org.apache.struts.util.PropertyMessageResources.loadLocale(PropertyMessageResources.java:297)
org.apache.struts.util.PropertyMessageResources.getMessage(PropertyMessageResources.java:192)
org.apache.struts.util.MessageResources.getMessage(MessageResources.java:339)
org.apache.struts.util.MessageResources.getMessage(MessageResources.java:370)
org.apache.struts.util.MessageResources.getMessage(MessageResources.java:248)
org.apache.struts.action.RequestProcessor.processMapping(RequestProcessor.java:683)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:242)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1482)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:507)
javax.servlet.http.HttpServlet.service(HttpServlet.java:697)
javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
com.adventnet.authentication.ContextChangeDetector.doFilter(ContextChangeDetector.java:100)
org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:75)


note The full stack trace of the root cause is available in the Apache Tomcat/5.0.28 logs.


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Apache Tomcat/5.0.28

Thanks,

Cesar