PDF export fails on {children} macro

WARNING: MacroFilter: unable to format macro: children
java.lang.NullPointerException
at com.atlassian.confluence.renderer.radeox.macros.PageChildrenMacro.execute(PageChildrenMacro.java:50
)
at com.atlassian.confluence.renderer.radeox.filters.MacroFilter.handleMatch(MacroFilter.java:120)
at org.radeox.filter.regex.RegexTokenFilter.filter(RegexTokenFilter.java:91)
at org.radeox.filter.FilterPipe.filter(FilterPipe.java:169)
at com.atlassian.confluence.renderer.radeox.AbstractRenderEngine.render(AbstractRenderEngine.java:68)
at com.atlassian.confluence.importexport.impl.ExportRenderEngine.render(ExportRenderEngine.java:40)
at com.atlassian.confluence.importexport.impl.WikiExporter.exportWikiToXHtml(WikiExporter.java:69)
at com.atlassian.confluence.importexport.impl.WikiExporter.exportWikiToXslFo(WikiExporter.java:77)
at com.atlassian.confluence.importexport.impl.PdfExporter.convertWikiToXslFo(PdfExporter.java:152)
at com.atlassian.confluence.importexport.impl.PdfExporter.prepareExportTemplate(PdfExporter.java:137)
at com.atlassian.confluence.importexport.impl.PdfExporter.prepareExportXSLFo(PdfExporter.java:268)
at com.atlassian.confluence.importexport.impl.PdfExporter.doExportEntity(PdfExporter.java:166)
at com.atlassian.confluence.importexport.impl.AbstractRendererExporterImpl.exportPage(AbstractRenderer
ExporterImpl.java:143)
at com.atlassian.confluence.importexport.impl.AbstractRendererExporterImpl.doExport(AbstractRendererEx
porterImpl.java:109)
at com.atlassian.confluence.importexport.impl.PdfExporter.doExport(PdfExporter.java:84)
at com.atlassian.confluence.importexport.DefaultImportExportManager.exportAs(DefaultImportExportManage
r.java:75)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at org.springframework.aop.framework.AopProxyUtils.invokeJoinpointUsingReflection(AopProxyUtils.java:5
9)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvoca
tion.java:201)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.jav
a:176)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.ja
va:153)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.jav
a:196)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:135)
at $Proxy21.exportAs(Unknown Source)
at com.atlassian.confluence.importexport.actions.ExportPageAction.execute(ExportPageAction.java:74)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:173)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.DefaultWorkflowInterceptor.intercept(DefaultWorkflowInterceptor.
java:58)
at com.atlassian.confluence.core.ConfluenceWorkflowInterceptor.intercept(ConfluenceWorkflowInterceptor
.java:32)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.atlassian.confluence.core.ConfluenceValidationInterceptor.intercept(ConfluenceValidationInterce
ptor.java:18)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.atlassian.confluence.security.actions.PermissionCheckInterceptor.intercept(PermissionCheckInter
ceptor.java:40)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.DefaultActionProxy.execute(DefaultActionProxy.java:116)
at com.opensymphony.webwork.dispatcher.ServletDispatcher.serviceAction(ServletDispatcher.java:182)
at com.opensymphony.webwork.dispatcher.ServletDispatcher.service(ServletDispatcher.java:162)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:129)
at com.atlassian.confluence.util.profiling.ProfilingPageFilter.parsePage(ProfilingPageFilter.java:36)
at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:61)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at com.atlassian.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:161)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at com.atlassian.seraph.filter.LoginFilter.doFilter(LoginFilter.java:181)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at com.atlassian.johnson.filters.JohnsonFilter.doFilter(JohnsonFilter.java:96)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.springframework.orm.hibernate.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInVie
wFilter.java:83)
at com.atlassian.confluence.setup.SpringSessionInViewFilter.doFilterInternal(SpringSessionInViewFilter
.java:32)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:39)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at com.atlassian.util.profiling.filters.ProfilingFilter.doFilter(ProfilingFilter.java:132)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at com.atlassian.core.filters.AbstractEncodingFilter.doFilter(AbstractEncodingFilter.java:38)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.
java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.
java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2416)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.
java:643)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.
java:641)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.
java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.
java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:601)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.ja
va:392)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:565)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619)
at java.lang.Thread.run(Thread.java:536)