If a page contains several subsequent ampersands they aren't escaped using HTML entities in the rendered HTML. For instance:

a && b

is also in HTML rendered as:

a && b

whereas:

a & b

would be rendered as:

a & b

The browser (at least IE/6.0) can deal with this, but the page can't be exported as a PDF:

com.atlassian.confluence.importexport.ImportExportException: org.apache.velocity.exception.MethodInvocationException: Invocation of method 'exportWikiToXslFo' in class com.atlassian.confluence.importexport.impl.WikiExporter threw exception class com.atlassian.confluence.renderer.WikiRenderException : org.dom4j.DocumentException: Error on line 30 of document : The entity name must immediately follow the '&' in the entity reference. Nested exception: The entity name must immediately follow the '&' in the entity reference. at com.atlassian.confluence.importexport.impl.PdfExporter.generateXslFo(PdfExporter.java:204) at com.atlassian.confluence.importexport.impl.PdfExporter.doExportEntity(PdfExporter.java:136) at com.atlassian.confluence.importexport.impl.AbstractRendererExporterImpl.exportPage(AbstractRendererExporterImpl.java:119) at com.atlassian.confluence.importexport.impl.AbstractRendererExporterImpl.doExport(AbstractRendererExporterImpl.java:85) at com.atlassian.confluence.importexport.impl.PdfExporter.doExport(PdfExporter.java:80) at