Word 2007 form question

I have created a form, using the form controls in the Developer tab. The form is basically a table format, with cells having the ‘text field’ control, and the occassional ‘date picker’ control.

As I understand it, I need to Protect Document in order for the form elements to work properly.

I want to add a control that will allow users to drag and drop an email message into a table cell. I tried the standard ‘text field’ control, but that didn’t work. If I leave that cell blank, but the document is protected, so users can’t add anything into that cell.

Is there some sort of control I can use that will allow users to add an email message (in that format where you see the envelope and double click it to open)?

I hope that makes sense, I’m not very experienced with forms!