PDF files aren't inclued when exporting as Sitemap XML

Hi, I've got a web site that I want to create an xml site map for using the Sitemap generator. The tool seems to crawl my site fine. PDFs appear in the Sitemap list view. However, when I Export > Sitemap XML, the tool does not include URLs for PDF files. When I try exporting a "URL Raw List" or CSV file, I get the PDF files.

Has anyone else experienced this? The site has 191 pdfs with good content that I definitely want included and I'd rather not manually enter the xml nodes for all of those pdfs.

Thanks in advance...