Can't open attachments in Public Folders using OWA on Exchange 2003

I finally figured out how to use Public Folders.  I've thought of a great use for them within my organization (I think).  Just as a 'proof of concept', I recreated a small piece of a directory tree of one of our current projects from our 'share' drive.  In Windows Explorer, I just dragged files from the shared drive into the their corresponding folder that I had created in Public Folders in Outlook.  (It would be nice to be able to drag the whole tree and not have to re-create the folders manually.)  Anyway, now, users who are working on that project, and have access to e-mail via Outlook (local or remote), can access those files.  Furthermore, when working remote they can access those files without a need for a VPN connection.  Works great from the Outlook client.  Drill in to the public folder, find the 'message' (file) you want to open, double-click, boom!!  Attachment opens in the proper application.  Here's the problem... OWA.  I know it has limitations, but I still think it's a very useful tool.  The users without Outlook installed and running on their home machines agree.  In OWA, when I open Public Folders, I can see all of the files (messages) with their cute little Microsoft icons.  When I double-click a message, a new IE page opens and gives me a 'HTTP 403 Forbidden' error.  I get the same thing if I click the 'Content' tab for the public folder from inside ESM.  I've got full access (Owner) rights to the folder.  So does Administrator.  Any ideas?