Stacktrace if session times out in middle of build configuration wizard

If you are configuring a build and your session times out in the middle of the configuration wizard, when you try to continue you get the following error:

Stack Trace: java.lang.NullPointerException
at com.atlassian.bamboo.ww2.interceptors.BuildConfigurationInterceptor.intercept(BuildConfigurationInterceptor.java:102)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.atlassian.bamboo.ww2.interceptors.BuildConfigurationFromSessionInterceptor.intercept(BuildConfigurationFromSessionInterceptor.java:40)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.DefaultActionProxy.execute(DefaultActionProxy.java:113)
at com.opensymphony.webwork.dispatcher.DispatcherUtils.serviceAction(DispatcherUtils.java:233)
at com.opensymphony.webwork.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:198)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:118)
at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:52)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at com.opensymphony.webwork.dispatcher.ActionContextCleanUp.doFilter(ActionContextCleanUp.java:78)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:264)
at org.acegisecurity.intercept.web.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:107)
at org.acegisecurity.intercept.web.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:72)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at org.acegisecurity.ui.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:110)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at com.atlassian.bamboo.filter.SeraphLoginFilter.doFilter(SeraphLoginFilter.java:56)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:191)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at org.acegisecurity.util.FilterChainProxy.doFilter(FilterChainProxy.java:148)
at org.acegisecurity.util.FilterToBeanProxy.doFilter(FilterToBeanProxy.java:90)
at com.atlassian.bamboo.filter.BambooAcegiProxyFilter.doFilter(BambooAcegiProxyFilter.java:25)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at com.atlassian.bamboo.filter.LicenseFilter.doFilter(LicenseFilter.java:71)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at com.atlassian.johnson.filters.JohnsonFilter.doFilter(JohnsonFilter.java:91)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at com.atlassian.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:182)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at com.atlassian.seraph.filter.LoginFilter.doFilter(LoginFilter.java:177)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at org.springframework.orm.hibernate.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:174)
at com.atlassian.spring.filter.FlushingSpringSessionInViewFilter.doFilterInternal(FlushingSpringSessionInViewFilter.java:29)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:77)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at com.atlassian.bamboo.filter.CompressingFilter.doFilter(CompressingFilter.java:69)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at com.atlassian.bamboo.filter.RequestCacheThreadLocalFilter.doFilter(RequestCacheThreadLocalFilter.java:26)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:823)
at org.mortbay.jetty.servlet.WebApplicationHandler.dispatch(WebApplicationHandler.java:473)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:567)
at org.mortbay.http.HttpContext.handle(HttpContext.java:1565)
at org.mortbay.jetty.servlet.WebApplicationContext.handle(WebApplicationContext.java:635)
at org.mortbay.http.HttpContext.handle(HttpContext.java:1517)
at org.mortbay.jetty.plus.PlusWebAppContext.handle(PlusWebAppContext.java:158)
at org.mortbay.http.HttpServer.service(HttpServer.java:954)
at org.mortbay.http.HttpConnection.service(HttpConnection.java:814)
at org.mortbay.http.HttpConnection.handleNext(HttpConnection.java:981)
at org.mortbay.http.HttpConnection.handle(HttpConnection.java:831)
at org.mortbay.http.SocketListener.handleConnection(SocketListener.java:244)
at org.mortbay.util.ThreadedServer.handle(ThreadedServer.java:357)
at org.mortbay.util.ThreadPool$PoolThread.run(ThreadPool.java:534)