PDF Export Retrieves Images From JIRA Macros via the Display URL and not the Application URL

Steps to Reproduce

1. Create an Application Link between Confluence and JIRA
2. Set the Display URL to a non-existent address, or to a proxy address that is reachable from the client's browser, but not accessible from the Confluence Server itself (the whole point of having an Application URL / Display URL separation)
3. Create a page and add a JIRA issue into the page
4. Export the page to PDF

You will notice Errors such as these:

2014-03-22 17:57:51,167 WARN [http-8542-1] [confluence.extra.flyingpdf.ConfluenceExportUserAgent] getImageResource Could not retrieve image resource http://192.168.2.3:8614/jira614/images/icons/statuses/open.png during Confluence export
 -- url: /c542/spaces/flyingpdf/pdfpageexport.action | page: 1933317 | userName: admin | referer: http://localhost:8542/c542/display/GIE/sa+dasd+as+d+assad | action: pdfpageexport

It seems that the getImageResource will attempt to obtain /images/icons/statuses/open.png via the Display URL, and not the Application URL. The Confluence Server is unable to reach the Display URL, hence, the error

Workaround

Set the Display URL to a URL that the Confluence Server is able to reach