I attached an image to a page (jpg, which is vertically taller in its original size spanning more than one page (say A4) )
Then I tried to generate the pdf file for this page, which threw the error shown below. And this behavior is consistent.
If the same image is placed horizontally (rotated 90 deg), works fine.

Cause:
com.atlassian.confluence.importexport.ImportExportException: Error while generating PDF!
Stack Trace: [hide]
com.atlassian.confluence.importexport.ImportExportException: Error while generating PDF!
at com.atlassian.confluence.importexport.impl.PdfExporter.generatePDF(PdfExporter.java:205)
at com.atlassian.confluence.importexport.impl.PdfExporter.doExportEntity(PdfExporter.java:158)
at com.atlassian.confluence.importexport.impl.AbstractRendererExporterImpl.exportPage(AbstractRendererExporterImpl.java:145)
at com.atlassian.confluence.importexport.impl.AbstractRendererExporterImpl.doExport(AbstractRendererExporterImpl.java:111)
at com.atlassian.confluence.importexport.impl.PdfExporter.doExport(PdfExporter.java:84)
at com.atlassian.confluence.importexport.DefaultImportExportManager.exportAs(DefaultImportExportManager.java:113)
at sun.reflect.GeneratedMethodAccessor1779.invoke(Unknown Source)
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:61)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:149)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:116)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:56)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:138)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:152)
at $Proxy26.exportAs(Unknown Source)
at com.atlassian.confluence.importexport.actions.ExportPageAction.execute(ExportPageAction.java:108)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:168)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:35)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.opensymphony.xwork.interceptor.DefaultWorkflowInterceptor.intercept(DefaultWorkflowInterceptor.java:55)
at com.atlassian.confluence.core.ConfluenceWorkflowInterceptor.intercept(ConfluenceWorkflowInterceptor.java:33)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:35)
at com.atlassian.confluence.core.ConfluenceValidationInterceptor.intercept(ConfluenceValidationInterceptor.java:16)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:35)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.atlassian.confluence.security.actions.PermissionCheckInterceptor.intercept(PermissionCheckInterceptor.java:40)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.atlassian.confluence.pages.actions.PageAwareInterceptor.intercept(PageAwareInterceptor.java:84)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:35)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.atlassian.confluence.core.ConfluenceAutowireInterceptor.intercept(ConfluenceAutowireInterceptor.java:25)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:35)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:35)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.atlassian.confluence.util.XWorkTransactionInterceptor.intercept(XWorkTransactionInterceptor.java:133)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:35)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:165)
at com.opensymphony.xwork.DefaultActionProxy.execute(DefaultActionProxy.java:115)
at com.opensymphony.webwork.dispatcher.ServletDispatcher.serviceAction(ServletDispatcher.java:229)
at com.opensymphony.webwork.dispatcher.ServletDispatcher.service(ServletDispatcher.java:199)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:118)
at com.atlassian.confluence.util.profiling.ProfilingPageFilter.parsePage(ProfilingPageFilter.java:150)
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.atlassian.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:168)
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:181)
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:96)
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:170)
at bucket.custom.FlushingSpringSessionInViewFilter.doFilterInternal(FlushingSpringSessionInViewFilter.java:31)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:73)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.util.profiling.filters.ProfilingFilter.doFilter(ProfilingFilter.java:132)
at com.atlassian.confluence.util.error.ProfilingAndErrorFilter.doFilter(ProfilingAndErrorFilter.java:27)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.core.filters.gzip.GzipFilter.doFilter(GzipFilter.java:61)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.core.filters.AbstractEncodingFilter.doFilter(AbstractEncodingFilter.java:36)
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:214)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:152)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:118)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:535)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:799)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:705)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:577)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Thread.java:534)
Caused by: org.apache.fop.apps.FOPException: null:43:1500 No meaningful layout in block after many attempts. Infinite loop is assumed. Processing halted.
at org.apache.fop.fo.flow.Block.layout(Block.java:140)
at org.apache.fop.fo.flow.Block.layout(Block.java:257)
at org.apache.fop.fo.flow.Block.layout(Block.java:257)
at org.apache.fop.fo.flow.AbstractFlow.layout(AbstractFlow.java:154)
at org.apache.fop.fo.flow.AbstractFlow.layout(AbstractFlow.java:110)
at org.apache.fop.fo.pagination.PageSequence.makePage(PageSequence.java:400)
at org.apache.fop.fo.pagination.PageSequence.format(PageSequence.java:338)
at org.apache.fop.apps.StreamRenderer.render(StreamRenderer.java:262)
at org.apache.fop.fo.FOTreeBuilder.endElement(FOTreeBuilder.java:223)
at org.apache.xerces.parsers.AbstractSAXParser.endElement(Unknown Source)
at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanEndElement(Unknown Source)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown Source)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
at org.apache.xerces.parsers.DTDConfiguration.parse(Unknown Source)
at org.apache.xerces.parsers.DTDConfiguration.parse(Unknown Source)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
at org.apache.fop.apps.Driver.render(Driver.java:498)
at org.apache.fop.apps.Driver.run(Driver.java:565)
at com.atlassian.confluence.importexport.impl.PdfExporter.generatePDF(PdfExporter.java:199)
... 102 more

Referer URL: http://phu840.um.us.sbphrd.com:8980/adviceexchange/display/IKM/Suresh+Kadirvel
Build Information:
Uptime: 8 days, 23 minutes, 37 seconds
Version: 1.4.3
Build Number: 219
Server Information:
Application Server: Apache Tomcat/5.0.30
Servlet Version: 2.4
Database Dialect: net.sf.hibernate.dialect.HSQLDialect
Memory Information:
Total Memory: 510 MB
Free Memory: 131 MB
Used Memory: 379 MB
System Information:
System Date: Tuesday, 18 Oct 2005
System Time: 11:31:40
System Favourite Colour: Lime
Java Version: 1.4.2_03
Java Vendor: Sun Microsystems Inc.
JVM Version: 1.0
JVM Vendor: Sun Microsystems Inc.
JVM Implementation Version: 1.4.2_03-b02
Java Runtime: Java(TM) 2 Runtime Environment, Standard Edition
Java VM: Java HotSpot(TM) Client VM
User Name: aitadmin
User Timezone: US/Eastern
Operating System: SunOS 5.9
OS Architecture: sparc
Request
Information:
URL: http://phu840.um.us.sbphrd.com:8980/adviceexchange/pages/doexportpage.action

• Scheme: http
• Server: phu840.um.us.sbphrd.com
• Port: 8980
• URI: /adviceexchange/500page.jsp
• - Context Path: /adviceexchange
• - Servlet Path: /500page.jsp
• - Path Info: null
• - Query String: pageId=3335&type=TYPE_PDF
  Attributes:
• javax.servlet.forward.request_uri : /adviceexchange/pages/doexportpage.action
• javax.servlet.forward.context_path : /adviceexchange
• javax.servlet.forward.servlet_path : /pages/doexportpage.action
• javax.servlet.forward.path_info : /500page.jsp
• javax.servlet.forward.query_string : pageId=3335&type=TYPE_PDF
• javax.servlet.error.message : Error while generating PDF!
• javax.servlet.error.exception : com.atlassian.confluence.importexport.ImportExportException: Error while generating PDF!
• os_securityfilter_already_filtered : true
• _sitemesh_using_stream : false
• com.atlassian.johnson.filters.JohnsonFilter_already_filtered : true
• javax.servlet.error.request_uri : /adviceexchange/pages/doexportpage.action
• javax.servlet.error.status_code : 500
• _sitemesh_filterapplied : true
• javax.servlet.error.servlet_name : action
• webwork.valueStack : com.opensymphony.xwork.util.OgnlValueStack@1fed101
• javax.servlet.error.exception_type : class com.atlassian.confluence.importexport.ImportExportException
• atlassian.core.seraph.original.url : /pages/doexportpage.action?pageId=3335&type=TYPE_PDF
• loginfilter.already.filtered : true
• javax.servlet.jsp.jspException : com.atlassian.confluence.importexport.ImportExportException: Error while generating PDF!
• sessioninview.FILTERED : true
• com.atlassian.core.filters.gzip.GzipFilter_already_filtered : true
  Parameters:
• type = TYPE_PDF
• pageId = 3335
  Logging:
  0 log statements generated by this request.