Custom data file uploads are not saved when "Save Matching Contact" is clicked after dupe warning

First, see this forum thread: http://forum.civicrm.org/index.php?topic=9554

Summary: If you have a custom data profile that includes a file upload as for a field, if when you go to save/attach the document you get a duplicate contact warning and then you re-browse for the file and click "Save Matching Contact," the file is not uploaded or attached.

Expected result: the file should have been uploaded, saved and attached.

Reproduce:

1) Go here: http://drupal.demo.civicrm.org/civicrm/contact/add?reset=1&action=update&cid=125
2) Scroll down to "Donor Relationship and Documents" and browse to attach a document to field "Document 1" and click "Save"
3) A dupe warning will appear.
4) Browse for a file for "Document 1" again and then click "Save Matching Contact"
5) There is no error, but the file is not attached