Null Pointer error in GetReturnURL

Following exeption keeps occuring on opensource. Seems to be unable to retrieve build. Can't figure out a reliable way to reproduce. Possibly coming from Ajax requests.

2007-05-15 12:46:28,630 INFO [TP-Processor10] [AccessLogFilter] - http://opensource.bamboo.atlassian.com/build/viewNextBuildResults.action?buildKey=PYTH-MAIN&buildNumber=365&returnUrl=%2Fbuild%2FviewComments.action%3FbuildKey%3DPYTH-MAIN%26buildNumber%3D365 832769kb-15827kb 200ms
2007-05-15 12:46:29,234 ERROR [TP-Processor6] [DispatcherUtils] Could not execute action
java.lang.NullPointerException
at com.atlassian.bamboo.build.GotoBuildResult.getReturnUrl(GotoBuildResult.java:30)
at com.atlassian.bamboo.ww2.results.ReturnableRedirectResult.doExecute(ReturnableRedirectResult.java:28)
at com.opensymphony.webwork.dispatcher.WebWorkResultSupport.execute(WebWorkResultSupport.java:101)
at com.opensymphony.xwork.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:312)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:207)
at com.opensymphony.xwork.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:137)
at com.atlassian.bamboo.ww2.interceptors.BambooWorkflowInterceptor.doIntercept(BambooWorkflowInterceptor.java:33)
at com.opensymphony.xwork.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:81)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:115)
at com.atlassian.bamboo.ww2.interceptors.BambooValidationInterceptor.doIntercept(BambooValidationInterceptor.java:33)
at com.opensymphony.xwork.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:81)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.webwork.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:171)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.atlassian.bamboo.ww2.interceptors.BasePermissionCheckInterceptor.intercept(BasePermissionCheckInterceptor.java:38)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:151)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.atlassian.bamboo.ww2.interceptors.PaginationAwareInterceptor.intercept(PaginationAwareInterceptor.java:68)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.atlassian.bamboo.ww2.interceptors.StatisticsAwareInterceptor.intercept(StatisticsAwareInterceptor.java:42)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.atlassian.bamboo.ww2.interceptors.ResultsListAwareInterceptor.intercept(ResultsListAwareInterceptor.java:43)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.atlassian.bamboo.ww2.interceptors.TestCaseAwareInterceptor.intercept(TestCaseAwareInterceptor.java:43)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.atlassian.bamboo.ww2.interceptors.BuildAwareInterceptor.intercept(BuildAwareInterceptor.java:41)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:189)
at com.opensymphony.xwork.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:100)
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.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:118)
at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.opensymphony.webwork.dispatcher.ActionContextCleanUp.doFilter(ActionContextCleanUp.java:78)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.bamboo.filter.AccessLogFilter.doFilter(AccessLogFilter.java:51)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
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.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.bamboo.filter.LicenseFilter.doFilter(LicenseFilter.java:71)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.johnson.filters.JohnsonFilter.doFilter(JohnsonFilter.java:91)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:182)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.seraph.filter.LoginFilter.doFilter(LoginFilter.java:177)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
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.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.planetj.servlet.filter.compression.CompressingFilter.handleDoFilter(CompressingFilter.java:203)
at com.planetj.servlet.filter.compression.CompressingFilter.doFilter(CompressingFilter.java:193)
at com.atlassian.bamboo.filter.CompressingFilter.doFilter(CompressingFilter.java:65)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.bamboo.filter.RequestCacheThreadLocalFilter.doFilter(RequestCacheThreadLocalFilter.java:26)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:199)
at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:282)
at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:767)
at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:697)
at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:889)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Thread.java:595)