SharePoint 'Code blocks are not allowed in this file'

When trying to customise the GroupBoard Workspace ASPX pages I was getting the following error:

'Code blocks are not allowed in this file'

Thanks to this post on the MSDN forum we got past the problem:

<PageParserPaths>
    <PageParserPath VirtualPath="/pages/[file name].aspx" CompilationMode="Always" AllowServerSideScript="true" IncludeSubFolders="true" />
</PageParserPaths>