How to create a form for distrib. that allows you to attach a file?

I had created a form, distributed & collected via email so that if a document needed to be attached to the request, the user would be able to attach it and then send the email with the request and document. However, we're Lotus Notes, and mixed Acro 8 and 9, mixed Reader & Pro.

There are some headaches associated with this depending on the version of Lotus Notes client being used, so I am thinking I'll just have the form submitted to a shared network directory. This is an internal form, no worries there.

SO - how do I come up with a way / button / whatever to allow a document to be attached? The file is being submitted/stored as PDF, not xml or fdf.

Thanks !