Our dev team just installed Eclipse 3.2 and JBoss 4.0.5.GA on our local Window XP
machines.

When selecting a JSP page from within the Eclipse 3.2 IDE and then I right-click to "run on server" I am getting the following error:

HTTP Status 500 -

type Exception report
message
description The server encountered an internal error () that prevented it from
fulfilling this request.
exception
java.lang.NullPointerException
org.jboss.mx.loading.RepositoryClassLoader.findClass(RepositoryClassLoader.java:620)
java.lang.ClassLoader.loadClass(Unknown Source)
org.jboss.mx.loading.RepositoryClassLoader.loadClassImpl(RepositoryClassLoader.java:464)
org.jboss.mx.loading.RepositoryClassLoader.loadClass(RepositoryClassLoader.java:405)
java.lang.ClassLoader.loadClass(Unknown Source)
java.lang.ClassLoader.loadClassInternal(Unknown Source)
org.acegisecurity.ui.ntlm.NtlmProcessingFilter.onPreAuthentication(NtlmProcessingFilter.java:344)
org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:200)
org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
org.acegisecurity.ui.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:110)
org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:191)

org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
org.acegisecurity.util.FilterChainProxy.doFilter(FilterChainProxy.java:148)
org.acegisecurity.util.FilterToBeanProxy.doFilter(FilterToBeanProxy.java:90)
org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
note The full stack trace of the root cause is available in the Apache
Tomcat/5.5.20 logs.

It appears that the issue is that Eclipse will rebuild and redeploy the EAR
to JBoss while at the same time opening up IE and trying to load the JSP. JBoss
eventually will see the new EAR and it has to go through a process of unloading
the current EAR from memory and then reloading the new EAR. The error I see is
happening when JBoss unloads the current EAR from memory as far as I can tell.